Alternatively spliced mRNA

Van der Bliek AM, Baas F, Ten Houte DL, Kooiman PM, van d, V, Borst P. The human mdr3 gene encodes a novel P-glycoprotein homologue and gives rise to alternatively spliced mRNAs in liver. EMBO J 1987 6(11) 3325-3331. 

Burtis, K. C., and B. X. Baker, Drosophila double sex gene controls somatic sexual differentiation by producing alternatively spliced mRNAs encoding related sex-specific polypeptides. Cell 56 997-1010, 1989. 

Rachinsky, T. L, Camp, S., Li, Y., Ek-strom, J., Newton, M., Taylor, P. Molecular Cloning of Mouse Acetylcholinesterase Tissue Distribution of Alternatively Spliced mRNA Species. Neuron 1990, 5, 317-327. 

The unique fetal alternative splicing mRNA exon 4 products of 52-kDa Ro-encoding amino acids include a leucine zipper (Cl3). The leucine zipper is the major autoantigen epitope (B23, B33, D12, D14, F10, K4, Ml7, R9). 

In a screening of tumor cell lines for Ron, KATO-III, a gastric carcinoma cell line, was unique in that the predominant Ron band under reducing conditions was 165-kDa uncleaved, truncated Ron. This was in contrast to the products of other cells, which showed 170-kDa uncleaved Ron and the 150-kDa (3 chain of the normal disulfide-linked heterodimer. The unique A-Ron band was the product of an alternatively spliced mRNA that resulted in deletion of 147 bp of message coding for a segment of Ron (Collesi et al., 1996). When the cDNA of A-Ron was transfected into COS-1 cells, the product was uncleaved A-Ron, which was not expressed on the cell surface and which... 

More than 20 different Isoforms of fibronectin have been identified, each encoded by a different, alternatively spliced mRNA composed of a unique combination of fibronectin gene exons. Recent sequencing of large numbers of mRNAs... 

Isolated from various tissues and comparison of their sequences with genomic DNA has revealed that nearly 60 percent of all human genes are expressed as alternatively spliced mRNAs. Clearly, alternative RNA splicing greatly expands the number of proteins encoded by the genomes of higher, multicellular organisms. 

The predicted sequences of SR-BI proteins (509 amino acids) from different mammalian species share approximately 80% sequence identity. As for CD36, the bulk of the protein lies between the two hydrophobic plasma membrane-anchoring domains on the extracellular aspect of cells and contains a set of conserved cysteines. An alternatively spliced mRNA of SR-BI and its corresponding protein have been identified and designated SR-BII. SR-BII differs from SR-BI only in that the C-terminal 42 amino acids in the C-terminal cytoplasmic domain of SR-BI are replaced by 39 residues encoded by an alternatively spliced exon [31]. 

Ciossek, T. Millauer, B. Ullrich, A. Identification of alternatively spliced mRNAs encoding variants of MDKl, a novel receptor tyrosine kinase expressed in the murine nervous system. Oncogene, 10, 97-108 (1995)... 

Translation of alternatively spliced mRNAs leads to three PARC isoforms that differ in the A domain of the protein. Translation of all 18 exons results in a PARC of 111 kDa while splice variants omitting exon 1 or both exon 1 and 2 result in PARC isoforms of 102 kDa and 99 kOa, respectively. Transient overexpression of the respective PARC variants and subsequent immunofluorescence analysis revealed that the PARGlll is targeted to the nucleus while PARG102 and PARG99 are targeted to the cytoplasm. ... 

With a few exceptions little is known about the mechanistic details of how production of alternatively spliced mRNAs is regulated. However, it appears clear that the SR family of splicing factors partake in many regulated splicing events. SR proteins are highly phosphorylated, primarily within the RS domain. Thus, reversible RS domain phosphorylation has been shown to regulate SR protein... 

Mammalian poly(A) polymerases are commonly observed in multiple forms even from a single type of cells, possibly due to the presence of compartmentally distinct isozymes. Multiple enzyme forms may also arise from different degrees of phosphorylation (50). The cDNA cloning of the gene(s) for bovine poly(A) polymerase has shown that the bovine enzymes are apparently derived from two alternatively spliced mRNAs. 

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