• thylakoid membranes
  • Explanation of 'the complicated and visible with the simple and invisible' is particularly challenging for the thylakoid membranes of higher plant chloroplasts which form an elaborate continuous three-dimensional network comprised of regular cylindrical, tightly stacked membranes, the grana thylakoids that are interconnected with single stroma thylakoids whose outer membrane surface face the stroma. (royalsocietypublishing.org)
  • protein
  • Studies of the physical properties and phase behavior of lipids have shown that lipids can also play dynamic roles and can respond to changes in their environment by undergoing phase transitions, alterations in lipid- lipid and lipid-protein interactions, and by release or uptake of cations or protons. (springer.com)
  • Unperturbed cells express very little TF PCA despite the fact that TF, an integral membrane protein, is on the cell surface where it can bind zymogen factor VII (FVII) as well as activated FVII (FVIIa). (ahajournals.org)
  • In some cases, the hydrated region can extend much further, for instance in lipids with a large protein or long sugar chain grafted to the head. (wikipedia.org)
  • The plasma membranes of cells contain combinations of glycosphingolipids and protein receptors organised in glycolipoprotein microdomains termed lipid rafts. (wikipedia.org)
  • raft
  • The connections between these events are reviewed along with evidence that lipid raft association may also contribute to TF encryption. (ahajournals.org)
  • The extraction would take advantage of lipid raft resistance to non-ionic detergents, such as Triton X-100 or Brij-98 at low temperatures (e.g., 4 °C). When such a detergent is added to cells, the fluid membrane will dissolve while the lipid rafts may remain intact and could be extracted. (wikipedia.org)
  • cellular
  • The cell membrane has been the focus of much recent biochemical and biophysical research, primarily because of its role in cellular phenomena. (springer.com)
  • The cell membranes of almost all living organisms and many viruses are made of a lipid bilayer, as are the membranes surrounding the cell nucleus and other sub-cellular structures. (wikipedia.org)
  • As an extensionof this notion, we propose here a `Lipid World'scenario as an early evolutionary step in theemergence of cellular life on Earth. (springer.com)
  • On a subcellular level, the cell's smooth endoplasmic reticulum (SER) that appears to control the formation of some of the photonic reflectors in certain iridescent scales ( vide infra ) also controls within other cells a host of other cellular functions that may range from lipid assembly to some forms of bioluminescence. (royalsocietypublishing.org)
  • Many of these processes are mediated by extensive and intimate interactions of actin with cellular membranes. (wikipedia.org)
  • outer membrane
  • One common example of such a modification in nature is the lipopolysaccharide coat on a bacterial outer membrane, which helps retain a water layer around the bacterium to prevent dehydration. (wikipedia.org)
  • processes
  • Inparticular, the documented chemical rate enhancementswithin lipid assemblies suggest that energy-dependentsynthetic reactions could lead to the growth andincreased abundance of certain amphiphilic assemblies.We further propose that selective processes might acton such assemblies, as suggested by our computersimulations of mutual catalysis among amphiphiles. (springer.com)
  • cell
  • The method is also efficient for transdermal drug delivery and the transport of drugs, oligonucleotides, antibodies, and plasmids across cell membranes (Neumann et al. (biology-online.org)
  • The complex and energy consuming machineries needed to regulate and maintain this state imply that membrane asymmetry is a key property for proper function of the membrane and, in turn, the survival of the cell. (we-heraeus-stiftung.de)
  • Two hemichannels, joined together across a cell membrane comprise a Gap Junction channel. (wikipedia.org)
  • And in addition to building cuticular structures, the epidermal cell may have to secrete wax, cement and/or glandular products (see Neville (1975) for a comprehensive review of the biology and chemistry of insect cuticle). (royalsocietypublishing.org)
  • At gap junctions, the intercellular space is between 2 and 4 nm and unit connexons in the membrane of each cell are aligned with one another. (wikipedia.org)
  • When different connexins join together to form one connexon, it is called a heteromeric connexon Two hemichannels, joined together across a cell membrane comprise a Gap Junction channel. (wikipedia.org)
  • A cell's ability to dynamically form microfilaments provides the scaffolding that allows it to rapidly remodel itself in response to its environment or to the organism's internal signals, for example, to increase cell membrane absorption or increase cell adhesion in order to form cell tissue. (wikipedia.org)
  • Other enzymes or organelles such as cilia can be anchored to this scaffolding in order to control the deformation of the external cell membrane, which allows endocytosis and cytokinesis. (wikipedia.org)
  • biophysical
  • However, membrane microdomains were postulated in the 1970s using biophysical approaches by Stier & Sackmann and Klausner & Karnovsky. (wikipedia.org)
  • model
  • The first of these, a derivative of the Danielle model, (2) requires that the lipid component of the membrane be a bilayer in structure and contribute to the membrane its basic barrier properties. (springer.com)
  • Until recently, this apparently crucial property could hardly be addressed in model membrane studies since asymmetric models were available only to a very limited extent. (we-heraeus-stiftung.de)
  • Taken together,these concepts provide a theoretical framework, andsuggest experimental tests for a Lipid World model forthe origin of life. (springer.com)
  • Rietveld & Simons related lipid rafts in model membranes to the immiscibility of ordered (Lo phase) and disordered (Ld or Lα phase) liquid phases. (wikipedia.org)
  • stroma
  • The differentiation of the continuous thylakoid membrane into stacked grana thylakoids interconnected by single stroma thylakoids is a morphological reflection of the non-random distribution of photosystem II/light-harvesting complex of photosystem II, photosystem I and ATP synthase, which became known as lateral heterogeneity. (royalsocietypublishing.org)
  • chains
  • Due to the rigid nature of the sterol group, cholesterol partitions preferentially into the lipid rafts where acyl chains of the lipids tend to be more rigid and in a less fluid state. (wikipedia.org)
  • temperature
  • The bilayer can adopt a solid gel phase state at lower temperatures but undergo phase transition to a fluid state at higher temperatures, and the chemical properties of the lipids' tails influence at which temperature this happens. (wikipedia.org)
  • hypothesis
  • My challenge then was twofold: (i) to determine whether there were indeed two discrete photosystems as implied by Hill and Bendall's hypothesis and (ii) to ascertain whether these photosystems were associated with the fascinating stacked and/or non-stacked thylakoid membrane domains of higher plants. (royalsocietypublishing.org)
  • Consistent with this hypothesis, we localized Cod1p to the ER membrane. (rupress.org)