title: Lipids induce expression of serum-responsive transmembrane kinase EhTMKB1-9 in an early branching eukaryote Entamoeba histolytica.
abstract: Mechanisms underlying the initiation of proliferative response are known only for a few organisms, and are not understood for the medically important organisms including Entamoeba histolytica. The trans membrane kinase EhTMKB1-9 of E. histolytica is one of the early indicators of proliferation and its' expression is regulated by serum, one of the components necessary for cellular proliferation in vitro. In this study we show that bovine serum albumin (BSA) can induce EhTMKB1-9 expression in place of serum, and that both follow the same mechanism. Both serum and BSA use the same promoter element and the activation process is initiated through a PI3 kinase-mediated pathway. We further show that BSA activates EhTMKB1-9 due to the lipids associated with it and that unsaturated fatty acids are responsible for activation. These results suggest that lipid molecules are ligand(s) for initiation of a signaling system that stimulates EhTMKB1-9 expression.
authors.affiliation: School of Life Sciences, Jawaharlal Nehru University, New Delhi, India.
authors.forename: Shiteshu
authors.initials: S
authors.lastname: Shrimal
authors.forename: Arpita
authors.initials: A
authors.lastname: Saha
authors.forename: Sudha
authors.initials: S
authors.lastname: Bhattacharya
authors.forename: Alok
authors.initials: A
authors.lastname: Bhattacharya
mesh_terms: D000818:Animals; D015152:Blotting, Northern; D049109:Cell Proliferation; D004748:Entamoeba histolytica / Q000166:cytology / Q000201:enzymology*; D005455:Fluorescent Antibody Technique; D050356:Lipid Metabolism; D011494:Protein Kinases / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D012710:Serum Albumin, Bovine / Q000378:metabolism
chemical_list: D012710:Serum Albumin, Bovine; D011494:Protein Kinases