| First Author | Morrison BW | Year | 1995 |
| Journal | J Biol Chem | Volume | 270 |
| Issue | 5 | Pages | 2176-82 |
| PubMed ID | 7836447 | Mgi Jnum | J:22642 |
| Mgi Id | MGI:70501 | Doi | 10.1074/jbc.270.5.2176 |
| Citation | Morrison BW, et al. (1995) Mat-8, a novel phospholemman-like protein expressed in human breast tumors, induces a chloride conductance in Xenopus oocytes. J Biol Chem 270(5):2176-82 |
| abstractText | We recently identified a novel 8-kDa transmembrane protein, Mat-8, that is expressed in a subset of murine breast tumors. We have now cloned a cDNA encoding the human version of Mat-8 and show that it is expressed both in primary human breast tumors and in human breast tumor cell lines. The extracellular and transmembrane domains of Mat-8 are homologous to those of phospholemman (PLM), the major plasmalemmal substrate for cAMP-dependent protein kinase and protein kinase C in several different tissues. PLM, which induces chloride currents when expressed in Xenopus oocytes, contains consensus phosphorylation sites for both cAMP-dependent protein kinase A and protein kinase C in its cytoplasmic domain. In contrast, the cytoplasmic domain of Mat-8 contains no such consensus phosphorylation sites and is, in fact, unrelated to the cytoplasmic domain of PLM. RNA blot analysis reveals that Mat-8 and PLM exhibit distinct tissue-specific patterns of expression. We show that expression of Mat-8 in Xenopus oocytes induces hyperpolarization-activated chloride currents similar to those induced by PLM expression. These findings suggest that Mat-8 and PLM, the products of distinct genes, are related proteins that serve as Cl- channels or Cl- channel regulators but have different roles in cell and organ physiology. |
