SSR1 explained

Translocon-associated protein subunit alpha is a protein that in humans is encoded by the SSR1 gene.^[1]

The signal sequence receptor (SSR) is a glycosylated endoplasmic reticulum (ER) membrane receptor associated with protein translocation across the ER membrane. The SSR consists of 2 subunits, a 34-kD glycoprotein encoded by this gene and a 22-kD glycoprotein. This gene generates several mRNA species as a result of complex alternative polyadenylation. This gene is unusual in that it utilizes arrays of polyA signal sequences that are exclusively non-canonical.^[1]

Further reading

• Wei ML, Cresswell P . HLA-A2 molecules in an antigen-processing mutant cell contain signal sequence-derived peptides. . Nature . 356 . 6368 . 443–6 . 1992 . 1557127 . 10.1038/356443a0 . 1992Natur.356..443W . 4310708 .
• Vogel F, Hartmann E, Görlich D, Rapoport TA . Segregation of the signal sequence receptor protein in the rough endoplasmic reticulum membrane. . Eur. J. Cell Biol. . 53 . 2 . 197–202 . 1991 . 1964414 .
• Hartmann E, Görlich D, Kostka S, etal . A tetrameric complex of membrane proteins in the endoplasmic reticulum. . Eur. J. Biochem. . 214 . 2 . 375–81 . 1993 . 7916687 . 10.1111/j.1432-1033.1993.tb17933.x . 11858/00-001M-0000-0015-3BD2-F . free .
• Hartmann E, Prehn S . The N-terminal region of the alpha-subunit of the TRAP complex has a conserved cluster of negative charges. . FEBS Lett. . 349 . 3 . 324–6 . 1994 . 8050590 . 10.1016/0014-5793(94)00693-8 . 42968119 .
• Maruyama K, Sugano S . Oligo-capping: a simple method to replace the cap structure of eukaryotic mRNAs with oligoribonucleotides. . Gene . 138 . 1–2 . 171–4 . 1994 . 8125298 . 10.1016/0378-1119(94)90802-8 .
• Hu T, Guan T, Gerace L . Molecular and functional characterization of the p62 complex, an assembly of nuclear pore complex glycoproteins . J. Cell Biol. . 134 . 3 . 589–601 . 1996 . 8707840 . 10.1083/jcb.134.3.589 . 2120945 .
• Suzuki Y, Yoshitomo-Nakagawa K, Maruyama K, etal . Construction and characterization of a full length-enriched and a 5'-end-enriched cDNA library . Gene . 200 . 1–2 . 149–56 . 1997 . 9373149 . 10.1016/S0378-1119(97)00411-3 .
• Hirama T, Miller CW, Koeffler HP . Translocon-associated protein alpha transcripts are induced by granulocyte-macrophage colony-stimulating factor and exhibit complex alternative polyadenylation . FEBS Lett. . 455 . 3 . 223–7 . 1999 . 10437777 . 10.1016/S0014-5793(99)00885-6 . 9426244 .
• Wang L, Dobberstein B . Oligomeric complexes involved in translocation of proteins across the membrane of the endoplasmic reticulum . FEBS Lett. . 457 . 3 . 316–22 . 1999 . 10471800 . 10.1016/S0014-5793(99)01075-3 . 22341517 . free .
• Strausberg RL, Feingold EA, Grouse LH, etal . Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences . Proc. Natl. Acad. Sci. U.S.A. . 99 . 26 . 16899–903 . 2003 . 12477932 . 10.1073/pnas.242603899 . 139241 . 2002PNAS...9916899M . free .
• Zhang H, Li XJ, Martin DB, Aebersold R . Identification and quantification of N-linked glycoproteins using hydrazide chemistry, stable isotope labeling and mass spectrometry . Nat. Biotechnol. . 21 . 6 . 660–6 . 2003 . 12754519 . 10.1038/nbt827 . 581283 .
• Mungall AJ, Palmer SA, Sims SK, etal . The DNA sequence and analysis of human chromosome 6 . Nature . 425 . 6960 . 805–11 . 2003 . 14574404 . 10.1038/nature02055 . 2003Natur.425..805M . free .
• Gerhard DS, Wagner L, Feingold EA, etal . The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC) . Genome Res. . 14 . 10B . 2121–7 . 2004 . 15489334 . 10.1101/gr.2596504 . 528928 .
• Stelzl U, Worm U, Lalowski M, etal . A human protein-protein interaction network: a resource for annotating the proteome . Cell . 122 . 6 . 957–68 . 2005 . 16169070 . 10.1016/j.cell.2005.08.029 . 11858/00-001M-0000-0010-8592-0 . 8235923 . free .
• Otsuki T, Ota T, Nishikawa T, etal . Signal sequence and keyword trap in silico for selection of full-length human cDNAs encoding secretion or membrane proteins from oligo-capped cDNA libraries . DNA Res. . 12 . 2 . 117–26 . 2007 . 16303743 . 10.1093/dnares/12.2.117 . free .
• Olsen JV, Blagoev B, Gnad F, etal . Global, in vivo, and site-specific phosphorylation dynamics in signaling networks . Cell . 127 . 3 . 635–48 . 2006 . 17081983 . 10.1016/j.cell.2006.09.026 . 7827573 . free .

Notes and References

1. Web site: Entrez Gene: SSR1 signal sequence receptor, alpha (translocon-associated protein alpha).