1,722,078 research outputs found
(Biochem. Soc. Trans., 28:658-660)Polyunsaturated fatty acid specific elongation enzymes
No full textA role for SUMO modification in transcriptional repression and activation
Full text linkSince the discovery of the SUMO (small ubiquitin-related modifier) family of proteins just over a decade ago, a plethora of substrates have been uncovered including many regulators of transcription. Conjugation of SUMO to target proteins has generally been considered as a repressive modification. However, there are now a growing number of examples where SUMOylation has been shown to activate transcription. Here, we discuss whether there is something intrinsically repressive about SUMOylation, or if the outcome of this modification in the context of transcription will prove to be largely substrate-dependent. We highlight some of the technical challenges that will be faced by attempting to answer this question
Biochem Soc Trans
Full text linkThe functional characterization of all genes and their gene products is the main challenge of the postgenomic era. Recent experimental and computational techniques have enabled the study of interactions among all proteins on a large scale. In this paper, approaches will be presented to exploit interaction information for the inference of protein structure, function, signalling pathways and ultimately entire interactomes. Interaction networks can bemodelled as graphs, showing the operation of gene function in terms of protein interactions. Since the architecture of biological networks differs distinctly from random networks, these functional maps contain a signal that can be used for predictive purposes. Protein function and structure can be predicted by matching interaction patterns, without the requirement of sequence similarity. Moving on to a higher level definition of protein function, the question arises how to decompose complex networks into meaningful subsets. An algorithm will be demonstrated, which extracts whole signal-transduction pathways from noisy graphs derived from text-mining the biological literature. Finally, an algorithmic strategy is formulated that enables the proteomics community to build a reliable scaffold of the interactome in a fraction of the time compared with uncoordinated efforts
Biochem Soc Trans
Full text linkAccomplishment of the human and mouse genome projects resulted in accumulation of extensive gene sequence information. However, the information about the biological functions of the identified genes remains a bottleneck of the post-genomic era. Hence, assays providing simple functional information, such as localization of the protein within the cell, can be very helpful in the elucidation of its function. Transfected cell arrays offer a robust platform for protein localization studies. Open reading frames of unknown genes can be linked to a His6-tag or GFP (green fluorescent protein) reporter in expression vectors and subsequently transfected using the cell array. Cellular localization of the transfected proteins is detected either by specific anti-His-tag antibodies or directly by fluorescence of the GFP fusion protein and by counterstaining with organelle-specific dyes. The high throughput of the method in terms of information provided for every single experiment makes this approach superior to classical immunohistological methods for protein localization
Biochem. Soc. Trans.
No full textMeiosis creates haploid cells from diploid progenitors. Homologous chromosomes are moved, paired and segregated from each other in a specialized meiosis I division. A second division that lacks a preceding S-phase produces haploid cells. In prophase I, chromosomes attach with their telomeres to the nuclear envelope and undergo oscillating movements that become restricted to a limited nuclear sector during the widely conserved bouquet stage. Recent observations in budding yeast meiosis suggest that telomere clustering depends on actin, whereas exit from the bouquet stage requires meiotic cohesin. Telomere clustering may also be modulated by progression in recombination. These observations suggest that the unique meiotic nuclear topology and telomere dynamics are regulated at different levels
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