Mechanism of sperm. Medical search. Frequent questions

Motility is only achieved when the sperm presents a fully functional flagellum, is capable of producing energy to fuel the movement, and suffers epididymal maturation and capacitation. (bioone.org)
Since sperm is a transcriptionally silent cell, motility depends on the activation and/or inhibitions of key signaling pathways. (bioone.org)
This review describes and discusses the main signaling pathways involved in primary and hyperactivated motility, as well as the bioenergetic mechanisms necessary to produce energy to fuel sperm motility. (bioone.org)
Understanding the signaling pathways behind sperm motility can help pinpoint the cause of male infertility and uncover targets for male contraception. (bioone.org)
Sperm motility depends on energy availability, intact flagellum and the crosstalk of several signaling pathways that lead to an increase of tyrosine phosphorylation of key proteins. (bioone.org)
Maria João Freitas , Srinivasan Vijayaraghavan , and Margarida Fardilha "Signaling mechanisms in mammalian sperm motility," Biology of Reproduction 96(1), 2-12, (20 December 2016). (bioone.org)
Structural events and molecular mechanisms that promote mammalian sperm acrosomal exocytosis and motility. (uba.ar)
Of course, that might not be such bad advice, but why it might be reasonable advice has absolutely nothing to do with sperm counts, sperm motility, or infertility. (scienceblogs.com)
In aquatic habitats, gametes are released into the water where sperm acquire motility and navigate to the egg. (elifesciences.org)
However, the over production of oxygen free radicals in sperm membrane decreases the antioxidant defense activity thereby leading to low sperm motility and viability, DNA fragmentation and protein denaturation. (scialert.net)
Sperm motility is an important index for the evaluation of semen quality. (bvsalud.org)
Improving sperm motility is important to improve reproductive performance, promote breeding process, and reduce production cost. (bvsalud.org)
However, the molecular mechanisms regulating sperm motility in chickens remain unclear. (bvsalud.org)
In this study, histological observation and whole-transcriptome analysis were performed on testicular tissue of chickens with high and low sperm motility. (bvsalud.org)
Histological observations showed that roosters with high sperm motility exhibited better semen quality than those with low sperm motility. (bvsalud.org)
In addition, the germinal epithelial cells of roosters with low sperm motility were loosely arranged and contained many vacuoles. (bvsalud.org)
Among them, there were 417 differentially expressed mRNAs (DEmRNAs), 106 differentially expressed lncRNAs (DElncRNAs), and 15 differentially expressed miRNAs (DEmiRNAs) between high and low sperm motility testes. (bvsalud.org)
By integrating the competitive relationships between DEmRNAs, DElncRNAs, and DEmiRNAs, we identified the regulatory pathway of MSTRG.3077.3/MSTRG.9085.1-gga-miR-138-5p-CADM1 and MSTRG.2290.1-gga-miR-142-3p-GNAQ/PPP3CA as crucial in the modulation of chicken sperm motility. (bvsalud.org)
This study provides new insights into the function and mechanism of ceRNAs in regulating sperm motility in chicken testes. (bvsalud.org)

Obesity can affect spermatogenesis via several mechanisms and processes, among others via hormonal changes. (nature.com)
The importance of phosphorylation in sperm during spermatogenesis has not been pursued extensively. (cdc.gov)

Molecular mechanisms of sperm capacitation: progesterone-induced secondary calcium oscillations reflect the attainment of a capacitated state. (edu.au)
The incidence of such oscillations was dependent upon sperm capacitation and showed significant inter-individual variation. (edu.au)

Mammalian sperm cells present highly specific lipidic composition, high content of polyunsaturated fatty acids, plasmalogenes and sphingomyelins. (scialert.net)

Below is the crucial chart, which shows that "total motile count" - the number of sperm in the ejaculated semen - plunged 22 percent three to five months after the second shot (T2) and barely recovered during the final count (T3), when it was still 19 percent below the pre-shot level. (blogspot.com)
Out of these, 18% were diagnosed with a male-related infertility problem, 14% of which related to sperm or semen. (medicalnewstoday.com)
Semen was collected and evaluated from sexually mature males on a weekly schedule for 5 weeks to maximize sperm output. (cdc.gov)

A small secreted protein NICOL regulates lumicrine-mediated sperm maturation and male fertility. (news-medical.net)
Fertility experts are warning man that using a mobile for as little as an hour a day is "cooking sperm" and lowering level significantly. (scienceblogs.com)
Based on these findings, it was proposed that oxidative stress induced by excessive ROS may trigger sperm apoptosis through mitochondrial impairment, resulting in decreased fertility in mice exposed to fluoride. (fluoridealert.org)
Based on counts from men who donated sperm to three fertility clinics in Israel, this finding is devastating - medically and politically. (blogspot.com)

The overall goal of this proposal is to apply our diverse suite of genetic, molecular, and biophysical tools to gain mechanistic insights into normal sperm chromatin packaging, which is essential for genome fidelity and reproductive fitness of the species. (hhs.gov)
Research Interests: Mechanisms involved in the production of normal sperm and eggs. (csuohio.edu)
Since, ROS is essential for the normal sperm physiology, rationale use of antioxidants is advocated. (scialert.net)

They claim the effect is down to 'cryptic female choice' where an internal mechanism in the reproductive tract favours the sperm from males that are most genetically different to them. (dailymail.co.uk)
When placed in a three-dimensional mock-up of the female reproductive tract, bull sperm - which are similar to human sperm - appear to team up in groups of two to four cells. (newscientist.com)
This is an important advance in explaining how sperm become hypermotile in the female reproductive tract. (medicalnewstoday.com)

The male gamete, sperm, needs to mature in a tube called the epididymis before it can become a viable cell for fertilization. (news-medical.net)
suspect that this unusual swimming behaviour guides sperm through a small hole in the protective coating of fish eggs, which eventually leads to fertilization. (elifesciences.org)
And then, upon fertilization, that egg and that sperm meet and the marks are erased again. (the-scientist.com)
Soon after fertilization, the vast majority of methylcytosine in sperm is converted by the Tet3 enzyme to hydroxymethylcytosine that gets lost by dilution during replication, effectively erasing cytosine methylation patterns except for a subset that is maintained, including those of some imprinted genes. (i-sis.org.uk)
After fertilization, the sperm genome is rapidly stripped of protamines and most, but not all histones. (i-sis.org.uk)
The authors conclude: "Progesterone-activated endocannabinoid depletion by ABHD2 is a general mechanism by which progesterone exerts its genome-independent action and primes sperm for fertilization. (medicalnewstoday.com)
The most effective treatment is usually in vitro fertilization via intracytoplasmic sperm injection. (msdmanuals.com)

Now, in a study published in Nature Communications , researchers from Osaka University have furthered our understanding of sperm maturation. (news-medical.net)
The mechanisms underlying sperm maturation are relatively understudied and poorly understood. (news-medical.net)
To better understand the process of sperm maturation, researchers from Osaka University conducted experiments on mice. (news-medical.net)
before this technology was available it was challenging to study the mechanisms of sperm maturation. (news-medical.net)
A protein known to be important to sperm maturation is NELL2, a large protein secreted from the testis. (news-medical.net)
NELL2 travels to the epididymis and, similar to how a key interacts with a keyhole, binds to a receptor (ROS1) to signal for sperm maturation to begin. (news-medical.net)
NICOL forms a tight molecular complex with NELL2 and helps to control the maturation of sperm. (news-medical.net)
Without NICOL, NELL2 is unable to signal properly and sperm maturation is disrupted. (news-medical.net)
We found that mice lacking NICOL were sterile, which indicates that NICOL is required for the sperm-maturation pathway to work properly,' says lead author Daiji Kiyozumi. (news-medical.net)
The development of non-hormonal male contraceptives is one possibility, where NICOL would be targeted to inhibit sperm maturation. (news-medical.net)
Increasing the expression of NICOL and subsequently recovering sperm maturation could also potentially be used to treat certain cases of infertility. (news-medical.net)

The particular mechanism by which sea urchin sperm cells sense the temporal gradient has been recently identified as a natural implementation of the well-known adaptive controller known as extremum seeking. (wikipedia.org)
In sea urchin sperm, a cyclic nucleotide-gated K + channel (CNGK) mediates a cGMP-induced hyperpolarization that evokes Ca 2+ influx. (elifesciences.org)

The goal of sperm is to fertilize the oocyte. (bioone.org)
Sperm chemotaxis is a form of sperm guidance, in which sperm cells (spermatozoa) follow a concentration gradient of a chemoattractant secreted from the oocyte and thereby reach the oocyte. (wikipedia.org)
In sperm chemotaxis, the oocyte secretes a chemoattractant, which, as it diffuses away, forms a concentration gradient: a high concentration close to the egg, and a gradually lower concentration as the distance from the oocyte increases. (wikipedia.org)
A major unresolved issue in developmental biology is the precise mechanism whereby the sperm activates the oocyte. (umass.edu)
A major step forward came in 2002 with the discovery of a sperm-specific mammalian phospholipase C called phospholipase C zeta (PLCζ), which had the expected properties of the mammalian oocyte activation factor and was subsequently identified in other vertebrate groups. (umass.edu)
Despite these advances, many questions remain about the precise mechanism of action of PLCζ and the extent of its role during oocyte activation in the vertebrate kingdom. (umass.edu)

We then consider recent data from this and other laboratories on the responses of sperm to three compounds: progesterone and nitric oxide (both products of the cumulus oophorus) and 4-aminopyridine. (dundee.ac.uk)
Sperm, which are about 50 µm long, respond to progesterone via a calcium channel. (acs.org)
Specialized cells that surround and nourish egg cells release progesterone, which makes calcium ions rush into human sperm. (acs.org)
The new research suggests that progesterone works by opening a pH-sensitive calcium channel called CatSper, which resides on sperm tail membranes. (acs.org)
Unconventional endocannabinoid signaling governs sperm activation via sex hormone progesterone. (acsh.org)
Next, they exposed the sperm to progesterone. (medicalnewstoday.com)
Eventually, using modified progesterone, the team isolated the enzyme alpha/beta hydrolase domain containing protein 2 (ABHD2) from the sperm tails. (medicalnewstoday.com)
With the ABHD2 inactivated, progesterone was unable to activate the sperm cells. (medicalnewstoday.com)

Sperm chemotaxis was demonstrated in a large number of non-mammalian species, from marine invertebrates to frogs. (wikipedia.org)
The molecular mechanism of sperm chemotaxis is still not fully known. (wikipedia.org)
Calcium signalling plays a pivotal role in sperm physiology, being intimately involved in the regulation of acrosome reaction, chemotaxis and hyperactivation. (dundee.ac.uk)

Microarray analysis also provided several important biological clues for further investigating fluoride-induced damage in sperm morphology and functions. (fluoridealert.org)
The morphology of their female reproductive system is complicated, with two sperm storage organs, the copulatory bursa and the seminal receptacle. (springer.com)

Nor is it impossible, as has been claimed, because there may be biological mechanisms behind cancer that we do not yet understand, and it's almost always physicists with little knowledge of epigenetics and other mechanisms of cancer development who make such dogmatic claims. (scienceblogs.com)
Hence, this chapter summarizes the biological plausibility of EDCs exposure and elucidates the mechanism of action underlying EDCs affecting the regulatory circuits of the mammalian HPG axis and reproductive function. (intechopen.com)
Understanding these propulsion mechanisms opens an avenue for the control of biological systems and the design of artificial nanomachines, with a major impact on various research areas ranging from life science and material science to environmental science. (fz-juelich.de)
However, macroscale biological swarms are governed by other mechanisms, and are therefore outside the focus of this priority programme. (fz-juelich.de)
It is characterized by abnormal sperm and leads to an inability to father biological children (infertility). (medlineplus.gov)

The exciting research, published in Science , reveals the molecular mechanism of DNA methylation reprogramming in the male germline of plants. (jic.ac.uk)
The molecular mechanism our work revealed pushes our understanding of de novo DNA methylation to the next level, showing how new methyl marks are established at specific sites in specific cells. (jic.ac.uk)
The research team wants to discover the molecular mechanism that transfers such traits through the DNA in sperm. (usu.edu)
In this study, I further unraveled the molecular mechanism of mDia activation in TCR signaling. (nii.ac.jp)

Despite the miniscule concentrations of the individual components, cocktails of endocrine disruptors, such as those found in blood, have a pronounced action in sperm. (innovations-report.com)
Synergistic activation of CatSper Ca2+ channels in human sperm by oviductal ligands and endocrine disrupting chemicals. (innovations-report.com)
In the case of environmental toxins, Michael Skinner's reproductive biology lab at Washington State University Pullman in the United States first reported in 2005 that injecting pregnant rats with endocrine disruptor fungicide vinclozolin caused sperm abnormalities that persisted in the male progeny for at least 4 generations [4]. (i-sis.org.uk)

The Israeli paper offers hard evidence that the vaccines may present a systemic risk to men's sperm counts. (blogspot.com)

It can be used to study blood cells, neurons, or - as in this case - plant sperm. (concordia.ca)

Scientists have discovered the "switch" that activates sperm cells to travel to the egg, potentially paving the way for new methods of male contraception and infertility treatment. (medicalnewstoday.com)
The findings may give hope to people affected by infertility due to low sperm mobility. (medicalnewstoday.com)
Earlier this year, Medical News Today reported that stem cells could be used to create sperm in order to overcome male infertility that results when meiosis does not occur. (medicalnewstoday.com)
Another rare mechanism of infertility is destruction or inactivation of sperm by sperm antibodies, which are usually produced by the man. (msdmanuals.com)

In sperm of marine invertebrates and mammals, Ca 2+ signalling has been intensely studied, whereas for fish little is known. (elifesciences.org)

As germline (eggs and sperm) cells develop some of the methyl markers are reset, affecting the information passed onto the next generation. (jic.ac.uk)
Inside the plant's male reproductive parts (the anthers), cells that will divide to produce the sperm (meiocytes) are surrounded by cells that nourish them. (jic.ac.uk)
This discovery changes the way we think about epigenetic inheritance across generations in plants by showing that small RNAs produced by germline nurse cells can determine the DNA methylome in the sperm. (jic.ac.uk)
Here we describe briefly the mechanisms of calcium regulation in somatic cells and the ways in which these mechanisms have been adapted to function in mature spermatozoa. (dundee.ac.uk)
Abstract Unlike oocytes (and all somatic cells), which package their DNA with histones, the DNA of mature sperm is bound by protamines, a highly basic and rapidly evolving protein that is essential for compaction of the paternal genome. (hhs.gov)
If you are moaning once again about your suitcase being far too small as your vacation approaches, you should take human sperm cells as an inspiration. (idw-online.de)
In sperm cells, however, it is enormously compressed. (idw-online.de)
If DNA were to take up as much space as a watermelon under normal circumstances, sperm cells would then only be as big as a tennis ball,' says Prof. Dr. Hubert Schorle from the Institute of Pathology at the University Hospital Bonn. (idw-online.de)
In a nutshell (no pun intended), preventing a single egg cell from being fertilized is simpler than deactivating the 40 million to 1.2 billion sperm cells found in a single ejaculation. (acsh.org)
In order to swim, sperm cells rely on special membrane proteins, called ion channels, that regulate ion flow. (acsh.org)
Some ion channels, however, are unique to sperm cells, and these could be attractive targets. (acsh.org)
In general, sperm cells become attracted to egg cells by various chemical or physical signals. (elifesciences.org)
In 2009, researchers identified a potassium ion channel, called CNGK, that starts the electrical signal in the sperm cells of sea urchins. (elifesciences.org)
This channel is activated by signalling molecules inside cells, called 'cyclic nucleotides', and its activity ultimately leads to calcium ions flowing into the sperm cell's tail. (elifesciences.org)
including some of the researchers involved in the 2009 work - now report that the CNGK channel also exists in the sperm cells of a freshwater fish, the zebrafish. (elifesciences.org)
Unexpectedly, the CNGK channel is located in the heads of this fish's sperm cells rather than in the tails. (elifesciences.org)
These findings suggest that while channel proteins found in sperm cells from different species look similar and serve similar roles, they are activated in ways that can be very different. (elifesciences.org)
This unusual structure of sperm membrane is responsible for its flexibility and the functional ability of sperm cells. (scialert.net)
Even more importantly, the fall in sperm counts CANNOT be blamed on short- or even medium-term inflammation as mRNA-generated spike proteins causes our immune cells to ramp up the systemic production of anti-spike antibodies. (blogspot.com)
Interest in working with the naive phenotype is strong because naive cells are able to originate even gametes [egg cells and sperm]. (eurekalert.org)
Sperm cells are not very mobile. (medicalnewstoday.com)
In affected males, almost all sperm cells have abnormally large and misshapen heads. (medlineplus.gov)
Because of the additional genetic material, if one of these abnormal sperm cells combines with an egg cell, the embryo will not develop or the pregnancy will result in miscarriage. (medlineplus.gov)
In the testes, this protein regulates the division of sperm cells. (medlineplus.gov)
This lack of aurora kinase C blocks cell division in sperm cells. (medlineplus.gov)
Without cell division, the chromosomes are not split among multiple new sperm cells. (medlineplus.gov)
As a result, affected sperm cells contain extra chromosomes, usually four copies of each instead of the usual one. (medlineplus.gov)
To elucidate the mechanism, primary T cells were isolated from the spleen and it was observed that BEZ235@NP treatment resulted in the arrest of these cells in the G0/G1 phase. (bvsalud.org)

Fluoride-induced apoptosis and gene expression profiling in mice sperm in vivo. (fluoridealert.org)
This study was conducted to evaluate ultrastructure, oxidative stress, and apoptosis in sperm of mice treated with 150 mg/l NaF for 49 days. (fluoridealert.org)
Furthermore, microarray analysis was also utilized to characterize the effects of fluoride in gene expression profiling on mice sperm. (fluoridealert.org)
An increased ROS and a decreased TAC accompanied with distinct morphological changes and significant apoptosis were observed in mice sperm from the fluoride group. (fluoridealert.org)

Additionally, instead of having one tail (flagellum) per sperm cell, affected sperm have multiple flagella, most often four. (medlineplus.gov)

In order for the sperm cell to increase mobility, calcium must also pass through its outer membrane and enter the "tail," or flagella, which it uses to propel itself along. (medicalnewstoday.com)

Oxygen free radicals are naturally produced by mitochondrial and sperm plasma membrane and have beneficial and detrimental effects that cannot be overlooked. (scialert.net)

No motile sperm were DENV positive. (cdc.gov)

To examine this fundamental yet poorly understood process we have developed novel genetic and biophysical tools to identify proteins implicated in the histone-to-protamine exchange and to dissect the molecular mechanisms of chromatin reorganization during spermiogenesis. (hhs.gov)
Since protamine packaging results in a super-condensed chromatin state, which does not easily lend itself to mechanistic investigations in vivo, we have developed novel methods to purify protamines from sperm to use in both in vitro DNA curtain assays and in vitro reconstitution assays of the histone-to-protamine exchange process. (hhs.gov)
We examined sperm DNA damage and chromatin condensation and measured plasma levels of leptin, testosterone, cholesterol and triglycerides. (nature.com)

These findings support the possibilities that DENV is sexually transmissible for a short period after acute dengue illness and that acute dengue induces reversible alterations in sperm. (cdc.gov)
However, the authors qualified their findings by reporting that after five months, sperm levels recovered. (blogspot.com)

For the calcium to enter, a sperm protein known as CatSper needs to join with similar proteins in the flagella. (medicalnewstoday.com)
The team first exposed sperm to a chemical that inhibits a particular class of enzyme, because they suspected that the molecule that acts on CatSper might feature within that class of enzymes. (medicalnewstoday.com)
They noted that the sperm remained inactive, suggesting that CatSper was not directly involved in the process. (medicalnewstoday.com)

To counteract the negative effects of excess ROS, spermatozoa and seminal plasma have several mechanisms to neutralize free radicals. (scialert.net)
To counteract oxidative damage, spermatozoa and seminal plasma have several mechanisms to neutralize free radicals. (scialert.net)

Finally we consider the nature of calcium signalling pathways in sperm. (dundee.ac.uk)

In zebrafish sperm, a more alkaline pH inside the cell causes calcium ions to flow in and this influx of calcium ions triggers a unique spinning-like swimming movement that is different from the swimming of other sperm from other species. (elifesciences.org)

Then the methylation comes back again in egg-specific marks and sperm-specific marks. (the-scientist.com)
Subsequently, they found that insecticides DDT and permethrin, jet fuel, plastic additives phthalates and bisphenol A, and dioxin can all trigger trans-generational health effects in rats such as obesity and ovarian disease, and each resulted in a different pattern of methylation in sperm DNA, according to Skinner. (i-sis.org.uk)
H3K9me2 was found at several paternally methylated imprinted regions in sperm, suggesting that this histone mark signals special sites of the paternal genome where methylation is maintained. (i-sis.org.uk)

In mammals, most histone proteins are lost during sperm development, eventually to be replaced by protamines. (i-sis.org.uk)

They found that when the C. elegans were mating competitively in an environment without hermaphrodites their sperm quickly evolved to be larger and more aggressive. (iflscience.com)
It was originally thought that simultaneous hermaphroditism was favoured by selection under low density, such as in deep-sea fishes, or low mobility, such as snails, and that sperm competition had little importance in simultaneous hermaphrodites (Ghiselin 1969 ). (springer.com)
Together, these characteristics indicate the existence of intense sperm competition among simultaneous hermaphrodites as well as in gonochorists. (springer.com)

The "spinning" mode probably guides sperm into the micropyle, a narrow entrance on the surface of fish eggs. (elifesciences.org)
In most species, the male uses a specially adapted arm to deliver a bundle of sperm directly into the female's mantle cavity, after which he becomes senescent and dies, while the female deposits fertilised eggs in a den and cares for them until they hatch, after which she also dies. (wikipedia.org)
Despite their small size, nematode sperm is actually much larger than human sperm, and it is thought that the sperm from different males literally battle it out inside the female for access to her eggs," says Phillips. (iflscience.com)

However, many simultaneously hermaphroditic nudibranchs have both an allo-sperm storage organ (the seminal receptacle) and an allo-sperm digesting organ (the copulatory bursa), suggesting the possibility of the occurrence of sperm competition. (springer.com)

In the meiocytes, these small RNAs also target genes with similar DNA sequences as the source transposons, helping to control gene expression and facilitate meiosis, a type of cell division that leads to the production of sperm. (jic.ac.uk)

Sperm cell membranes are high in polyunsaturated fatty acids and are sensitive to oxygen free radical induced damage mediated by lipid peroxidation. (scialert.net)
The head of the sperm cell contains the male's genetic information that is to be passed on to the next generation. (medlineplus.gov)
In men with macrozoospermia, the sperm cell head contains extra chromosomes, usually four copies of each instead of the usual one. (medlineplus.gov)
This additional genetic material accounts for the larger head size of the sperm cell. (medlineplus.gov)

Various mechanisms by which a stable propagation of changes in gene expression that is passed from egg and sperm to the embryo persists via epigenetic changes, e.g. (bvsalud.org)

All of these compounds induce calcium signals in the posterior sperm head and neck region and, when applied at appropriate concentrations, modify flagellar activity, causing asymmetric bending of the proximal flagellum. (dundee.ac.uk)

Also, it's easier to block ovulation than sperm production . (acsh.org)

The chemicals impair the function of human sperm. (innovations-report.com)

however, little is known about the molecular mechanisms by which fluoride exerts its toxic effects. (fluoridealert.org)

Sperm quantity and quality are key features explaining intra- and interspecific variation in male reproductive success. (jyu.fi)
During mating, they simultaneously play "male roles" as sperm donors and "female roles" as sperm recipients, in principle. (springer.com)
The AURKC gene provides instructions for making a protein called aurora kinase C. This protein is abundant in male testes, which are the male reproductive organs in which sperm are produced and stored. (medlineplus.gov)
Vinclozolin (Vin) has been shown to be an anti-androgen affecting male offspring in rats in utero, and its mechanism of action may be mediated by inhibition of androgenic receptor action. (cdc.gov)

So far, most sperm chemoattractants that have been identified in non-mammalian species are peptides or low-molecular-weight proteins (1-20 kDa), which are heat stable and sensitive to proteases. (wikipedia.org)
The oscillations were dependent upon the influx of extracellular calcium via mechanisms that were insensitive to inhibitors of L-type voltage operated calcium channels (nifedipine, verapamil, diltiazem), G-proteins (pertussis toxin) or the GABA (A) receptor (bicuculline). (edu.au)

Earlier this year, the lab also published a paper in the journal Science , which elucidated some of the molecular mechanisms behind sperm activation . (acsh.org)
Targeting it, therefore, should (once again, in theory) produce few side effects, while blocking the activation of sperm. (acsh.org)
A picture is emerging of sperm channel orthologues that employ different activation mechanisms and serve different functions. (elifesciences.org)

During sperm production, an enormous amount of DNA has to be packed into a very small space without breaking anything. (idw-online.de)
The Bowdoin team blocked the gene for sperm production in C. elegans to make some female, and mated these with the rare males for 60 generations. (iflscience.com)

Anatomy48

Organisms35

Diseases14

Chemicals and Drugs53

Analytical, Diagnostic and Therapeutic Techniques and Equipment47

Psychiatry and Psychology7

Phenomena and Processes63

Disciplines and Occupations1

Anthropology, Education, Sociology and Social Phenomena2

Technology, Industry, Agriculture4

Information Science4

Named Groups1

Health Care4

Motility19

Spermatogenesis2

Capacitation2

Mammalian sperm1

Semen3

Fertility4

Normal sperm3

Reproductive tract3

Fertilization7

Maturation11

Urchin2

Oocyte6

Progesterone8

Chemotaxis3

Morphology2

Biological5

Molecular mechanism4

Endocrine3

Men's sperm1

Plant sperm1

Infertility4

Marine invertebrates1

Cells28

Mice4

Additionally1

Tail1

Mitochondrial1

Motile1

Chromatin3

Findings2

CatSper3

Spermatozoa2

Pathways1

Calcium ions1

Methylation3

Protamines1

Hermaphrodites3

Eggs3

Seminal1

Genes1

Cell4

Embryo1

Induce1

Ovulation1

Human1

Exerts1

Male4

Proteins2

Activation3

Production2