Kinase Subfamily FAM198
FAM198 is a subfamily of the GASK (Golgi-Associated Kinase) family of secretory kinases. It consists of two genes (FAM198A/C3orf41 and FAM198B/C4orf18) in vertebrates, and one or more homologs in other deuterostomes. The proteins are likely to be catalytically inactive, and are virtually unstudied.
Like other FJ family kinases, many FAM198 members have a conserved signal peptide, and many have a TM region just downstream. A weakly-conserved 100-200 AA N-terminal region is then followed by the C-terminal kinase domain. The kinase domain lacks strong similarity to the other FJ subfamilies within the catalytic loop, though it probably conserves the K72-E91 salt bridge and the D184 Mg-co-ordinating residue.
No protein interactions have been reported for any member of this family (Feb 2012), and no phosphorylation has been seen.
Two members, FAM198A and FAM198B are found in all vertebrates, and several other members are seen in other deuterostomes, including Branchiostoma, Saccoglossus, and the sea urchin, S. purpuratus.
Expression and Function
No FAM198 has been functionally characterized. The expression of FAM198B in mouse and Xenopus was reported, and shown to be downstream of FGF and maybe basement membrane signaling . A GFP-fusion of FAM198B was reportedly localized in the Golgi, similar to the localization of FJX1, and supporting the predicted Signal Peptide . However, data from the Protein Atlas show localization of human FAM198B to the nucleus.
- Meszaros R, Strate I, Pera EM, and Durbeej M. Expression of the novel gene Ened during mouse and Xenopus embryonic development. Int J Dev Biol. 2008;52(8):1119-22. DOI:10.1387/ijdb.082700rm |
- Simpson JC, Wellenreuther R, Poustka A, Pepperkok R, and Wiemann S. Systematic subcellular localization of novel proteins identified by large-scale cDNA sequencing. EMBO Rep. 2000 Sep;1(3):287-92. DOI:10.1093/embo-reports/kvd058 |