Search results for "Biogenesis"
showing 10 items of 150 documents
Identification and characterization of the nano-sized vesicles released by muscle cells
2013
AbstractSeveral cell types secrete small membranous vesicles that contain cell-specific collections of proteins, lipids, and genetic material. The function of these vesicles is to allow cell-to-cell signaling and the horizontal transfer of their cargo molecules. Here, we demonstrate that muscle cells secrete nano-sized vesicles and that their release increases during muscle differentiation. Analysis of these nanovesicles allowed us to characterize them as exosome-like particles and to define the potential role of the multifunctional protein Alix in their biogenesis.
Biogenesis of the Yeast Cell Wall
1984
Yeast cells are covered by a rigid structure that protects the protoplast from osmotic changes and gives the characteristic shape to the cell. Studies on the composition of the wall of several species of yeast and other fungi have shown that they contain mainly polysaccharides with minor amounts of other materials. A completely rigid and continuous wall, nevertheless, would render growth impossible because cell extension would be restricted, so that an equilibrium must exist between softening (partial degradation) of wall and incorporation of new material into free ends of the polymers. From these considerations, it seems clear that the walls must be structurally and enzymatically a complex…
Biogenesis of the Fungal Cell Wall
1994
Cell walls play essential roles in growth, development, and in interactions of fungi with the environment and with other cells. Besides its primary protective role in shielding the cell against osmotic, chemical, and biological harm, the wall is involved in many other functions including morphogenesis, and some activities that may be denominated as “social”, such as morphological responses, antigenic expression, adhesion, and cell-cell interaction (Peberdy 1990; Ruiz-Herrera 1992; Sentandreu et al. 1991). There are many data supporting the idea that temporal and spatial regulation of wall polymer synthesis and assembly are critical for the properties of the walls, which thus do not exclusiv…
Pigment Assembly—Transport and Ligation
2006
The ligation of pigments to proteins involved in photosynthesis appears to be strictly regulated and, in turn, to have an important regulatory impact on the biogenesis of the photosynthetic apparatus. Even so, the molecular mechanism of pigment-protein assembly is largely unknown. However, data are now accumulating on the co-translational transport of chlorophyll a proteins and the post-translational transport of chlorophyll a/b proteins into the thylakoid membrane. The molecular apparatus in the thylakoid membrane presumably occupied with protein insertion may also be involved in pigment ligation. Similarly, the last steps of pigment biosynthesis, whose location has not been fully establis…
IM30 IDPs form a membrane protective carpet upon super-complex disassembly
2020
AbstractMembers of thephage shock protein A(PspA) family, including theinner membrane-associated protein of 30 kDa(IM30), are suggested to stabilize stressed cellular membranes. Furthermore, IM30 is essential in thylakoid membrane-containing chloroplasts and cyanobacteria, where it is involved in membrane biogenesis and/or remodeling. While it is well known that PspA and IM30 bind to membranes, the mechanism of membrane stabilization is still enigmatic. Here we report that ring-shaped IM30 super-complexes disassemble on membranes, resulting in formation of a membrane-protecting protein carpet. Upon ring dissociation, the C-terminal domain of IM30 unfolds, and the protomers self-assemble on …
Comprehensive analysis of forty yeast microarray datasets reveals a novel subset of genes (APha-RiB) consistently negatively associated with ribosome…
2014
Background The scale and complexity of genomic data lend themselves to analysis using sophisticated mathematical techniques to yield information that can generate new hypotheses and so guide further experimental investigations. An ensemble clustering method has the ability to perform consensus clustering over the same set of genes from different microarray datasets by combining results from different clustering methods into a single consensus result. Results In this paper we have performed comprehensive analysis of forty yeast microarray datasets. One recently described Bi-CoPaM method can analyse expressions of the same set of genes from various microarray datasets while using different cl…
Comprehensive analysis of forty yeast microarray datasets reveals a novel subset of genes (APha-RiB) consistently negatively associated with ribosome…
2014
This article has been made available through the Brunel Open Access Publishing Fund. Background: The scale and complexity of genomic data lend themselves to analysis using sophisticated mathematical techniques to yield information that can generate new hypotheses and so guide further experimental investigations. An ensemble clustering method has the ability to perform consensus clustering over the same set of genes from different microarray datasets by combining results from different clustering methods into a single consensus result. Results: In this paper we have performed comprehensive analysis of forty yeast microarray datasets. One recently described Bi-CoPaM method can analyse express…
Out of fuzzy chemistry: from prebiotic chemistry to metabolic networks
2012
The origin of life on Earth was a chemical affair. So how did primitive biochemical systems originate from geochemical and cosmochemical processes on the young planet? Contemporary research into the origins of life subscribes to the Darwinian principle of material causes operating in an evolutionary context, as advocated by A. I. Oparin and J. B. S. Haldane in the 1920s. In its simplest form (e.g., a bacterial cell) extant biological complexity relies on the functional integration of metabolic networks and replicative genomes inside a lipid boundary. Different research programmes have explored the prebiotic plausibility of each of these autocatalytic subsystems and combinations thereof: sel…
ChemInform Abstract: Out of Fuzzy Chemistry: From Prebiotic Chemistry to Metabolic Networks
2012
The origin of life on Earth was a chemical affair. So how did primitive biochemical systems originate from geochemical and cosmochemical processes on the young planet? Contemporary research into the origins of life subscribes to the Darwinian principle of material causes operating in an evolutionary context, as advocated by A. I. Oparin and J. B. S. Haldane in the 1920s. In its simplest form (e.g., a bacterial cell) extant biological complexity relies on the functional integration of metabolic networks and replicative genomes inside a lipid boundary. Different research programmes have explored the prebiotic plausibility of each of these autocatalytic subsystems and combinations thereof: sel…
Vipp1: a very important protein in plastids?!
2011
As a key feature in oxygenic photosynthesis, thylakoid membranes play an essential role in the physiology of plants, algae, and cyanobacteria. Despite their importance in the process of oxygenic photosynthesis, their biogenesis has remained a mystery to the present day. A decade ago, vesicle-inducing protein in plastids 1 (Vipp1) was described to be involved in thylakoid membrane formation in chloroplasts and cyanobacteria. Most follow-up studies clearly linked Vipp1 to membranes and Vipp1 interactions as well as the defects observed after Vipp1 depletion in chloroplasts and cyanobacteria indicate that Vipp1 directly binds to membranes, locally stabilizes bilayer structures, and thereby ret…