Splicing of RNA

In mammalia, seven different members encoded by distinct genes have been identified, all of which are activated by a distinct set of cytokines. Diversity in signaling is provided by variants of STAT proteins derived from either alternative splicing of RNA transcripts or proteolytic processing (e.g., STATs 1,3,4, and 5) and the ability of certain STATs to form both homodimers and heterodimers with each other. In response to inteiferon-y monomeric STAT1 dimerizes, while upon interferon-a stimulation a heterotrimeric complex consisting of STAT 1 and STAT2 with associated... 

Splicing of RNA simultaneously discovered in Broker s and Sharp s laboratories. 

Figure 5.21 Splicing of RNA chains (gray lines) through a) intramolecular and b) intermolecular nucleophilic attack in the presence of a base [121].

Ribosomal RNA is the most abundant of the three types of RNA. Transfer RNA comes next, followed by messenger RNA, which constitutes only 5% of the total RNA. Eukaryotic cells contain additional small RNA molecules. Small nuclear RNA (snRNA) molecules, for example, participate in the splicing of RNA exons. A small RNA molecule in the cytosol plays a role in the targeting of newly synthesized proteins to intracellular compartments and extracellular destinations. 

Alternfitive splicing of RNA ejtcludE S mem be anfi-andinc ing x domain... 

Small nuclear RNA (snRNA) molecules participate m the splicing of RNA exons. 

Alternative splicing of RNA excludes membrane-anchoring domain... 

Houck, K.A., N. Ferrara, J. Winer, G. Cachianes, B. Li, and D.W. Leung. The vascular endothelial growth factor family identification of a fourth molecular species and characterization of alternative splicing of RNA. Mol Endocrinol 5 1806-14, 1991. 

Shtivelman, E. Lifshitz, B. Gale, R.P. Roe, B.A. Canaani, E. Alternative splicing of RNAs transcribed from the human abl gene and from the bcr-abl fused gene. Cell, 47, 277-284 (1986)... 

Reflect and Apply Explain how differential splicing of RNA is thought to be relevant to the information gathered from the Human Genome Project. 

Small nuclear RNA (snRNA) is found in the eukaryotic nucleus and is involved in splicing reactions of other RNA types. An snRNP is a small nuclear ribonucleoprotein particle. A complex of small nuclear RNA and protein catalyzes splicing of RNA. 

A proteome is the complete complement of translation products (i.e., polypeptides and proteins) that can be produced from the code held in an organism s genome. As for a transcriptome, a full proteome will include protein variants produced from individual genes by alternative splicing of RNA transcripts and alternative posttranslational modifications. 

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