Here we review recent insights into the biophysical, biochemical, and epigenetic processes that underlie regenerative healing in amphibians, focusing particularly on tail and limb regeneration in Xenopus . (frontiersin.org)
We examined the bioelectric properties (resting potential gradients in the epidermis) of Xenopus laevis froglets undergoing hindlimb amputation and observed that the contralateral (undamaged) limb exhibits apparent depolarization signals immediately after the opposite hindlimb is amputated. (biologists.com)
Xenopus tadpoles can regenerate their tails, limb buds and the lens of the eye, although the ability of the latter two organs to regenerate diminishes with advancing developmental stage. (biomedcentral.com)
Gene over-expression analyses in Xenopus limb and tail regeneration have indicated that successful regeneration requires the re-activation of developmental FGF or BMP signalling pathways [ 8 - 12 ]. (biomedcentral.com)
Amputation3
In mammals, a limb amputation or spinal cord transection is followed by inflammation and fibrotic scarring that leaves the animal with a permanent disability. (frontiersin.org)
The wound epithelium of N1 transgenic hindlimb buds, which forms over the cut surface of the limb bud after amputation, does not transition normally into the distal thickened apical epithelial cap. (biomedcentral.com)
N1 transgenic hindlimbs, which do not regenerate, do not form an apical epithelial cap or cone shaped blastema following amputation. (biomedcentral.com)
Urodele amphibians2
Glial Growth Factor and nerve-dependent proliferation in the regeneration blastema of urodele amphibians. (wikipedia.org)
In urodele amphibians such as axolotls and newts, the same injury is followed by scarless regenerative healing that can fully restore both the lost tissue and its function (reviewed in Tanaka, 2016 ). (frontiersin.org)
Regeneration10
He investigated cellular interactions in the mammalian peripheral nervous system, and the mechanisms underlying limb regeneration in salamanders. (wikipedia.org)
His work on limb regeneration included studies on dedifferentiation, nerve dependence of regeneration, positional identity, senescent cells, and regeneration as an evolutionary variable. (wikipedia.org)
The newt ortholog of CD59 is implicated in proximodistal identity during amphibian limb regeneration. (wikipedia.org)
Molecular basis for the nerve dependence of limb regeneration in an adult vertebrate.Science 330, 485-490 (2007). (wikipedia.org)
Here we try to elucidate the cellular aspects of regeneration by EdU incorporation in intact and posteriorly amputated annelid Alitta virens using quantitative analysis. (mdpi.com)
Elegant experiments using heat-shock inducible expression of inhibitory proteins have further refined these observations to establish epistatic relationships, in which BMP acts upstream of Wnt, which in turn acts upstream of FGF during regeneration of the limb bud and tail ( Lin and Slack, 2008 ). (frontiersin.org)
Epimorphic regeneration is the process by which complete regeneration of a complex structure such as a limb occurs through production of a proliferating blastema. (biomedcentral.com)
Furthermore, the underlying mesenchyme remains rounded and does not expand to form a cone shaped blastema, a normal feature of successful regeneration. (biomedcentral.com)
While all vertebrates are capable of some types of tissue regeneration, most, including humans, have lost the ability to regenerate whole structures such as limbs ( epimorphic regeneration ), [ 1 ]. (biomedcentral.com)
We have used this line to show that BMP function is not only required for appendage regeneration but that it is specifically needed to generate a proliferating blastema while being dispensable for wound healing [ 12 ]. (biomedcentral.com)
Among vertebrates1
Injuries that sever tissues such as the limb or spinal cord are met with radically different outcomes among vertebrates. (frontiersin.org)
Tissues2
The pattern of depolarization matches that of the amputated limb and is correlated to the position and type of injury, revealing that information about damage is available to remote body tissues and is detectable non-invasively in vivo by monitoring the bioelectric state. (biologists.com)
Once the wound is healed, the cells of the stump must mobilise under the wound epidermis and begin the process of replacing lost tissues, by forming a proliferating blastema. (biomedcentral.com)
Regeneration in salamanders1
He investigated cellular interactions in the mammalian peripheral nervous system, and the mechanisms underlying limb regeneration in salamanders. (wikipedia.org)
Regenerate3
Multiple cell types from the mature limb stump contribute to the blastema at different stages of regeneration, and we discuss the contribution of these types to the regenerate with reference to whether they are "pattern-forming" or "pattern-following" cells. (nih.gov)
BACKGROUND: Axolotls can regenerate their limbs. (bvsalud.org)
Q7) Which one of the following can regenerate its limb if lost by accident? (prexam.com)
Molecular3
Molecular basis for the nerve dependence of limb regeneration in an adult vertebrate.Science 330, 485-490 (2007). (wikipedia.org)
Much like a newt that has lost a limb, these mice will replace missing or damaged tissue with healthy tissue that lacks any sign of scarring," said the project's lead scientist Ellen Heber-Katz, Ph.D., a professor in Wistar's Molecular and Cellular Oncogenesis program. (eurekalert.org)
Increasing cellular and molecular understanding of regeneration in different animal species coupled with studies of adult neurogenesis in mammals is providing a basis for addressing this question. (nature.com)
Genes1
In their limb regeneration process, developmental genes are re-expressed and reorganize the developmental axes, in which the position-specific genes are properly re-expressed. (bvsalud.org)
Mechanisms2
In this review we focus on the crucial early events that occur during wound healing, the neural-epithelial interactions that drive the formation of the early blastema, and how these mechanisms differ from those of other species that have restricted regenerative potential, such as humans. (nih.gov)
The mechanisms responsible for this decay are both cell intrinsic, such as cellular senescence, as well as cell-extrinsic, such as changes in the regenerative environment. (mdpi.com)
Structures3
The axolotl is one of the few tetrapods that are capable of regenerating complicated biological structures, such as complete limbs, throughout adulthood. (nih.gov)
Upon injury the axolotl generates a population of regeneration-competent limb progenitor cells known as the blastema, which will grow, establish pattern, and differentiate into the missing limb structures. (nih.gov)
Figure 1: Different cellular modes of regenerating spinal cord structures after amputation. (nature.com)
Cell2
Newt myotubes re-enter the cell cycle by phosphorylation of the retinoblastoma protein. (wikipedia.org)
Unlike typical mammals, which heal wounds by forming a scar, these mice begin by forming a blastema, a structure associated with rapid cell growth and de-differentiation as seen in amphibians. (eurekalert.org)
We also discuss how the presence of cells from the different axes of the limb is required for the continued growth and establishment of pattern in the blastema as described in the polar coordinate model, and how this positional information is reprogrammed in blastema cells during regeneration. (nih.gov)
His work on limb regeneration included studies on dedifferentiation, nerve dependence of regeneration, positional identity, senescent cells, and regeneration as an evolutionary variable. (wikipedia.org)
Meanwhile, cellular studies ongoing at Wistar revealed that MRL cells behaved very differently than cells from "non-healer" mouse strains in culture. (eurekalert.org)