title: Modulation of sterol regulatory element binding protein-2 in response to rapid follicle development in chickens.
abstract: We investigated the expression profiles of sterol regulatory element binding proteins (SREBPs) and their related genes in chicken developing follicle membranes, from the small white follicle (SWF) stage to the Follicle 1 (F1) stage. Expression of SREBP-2 was significantly increased in the rapid stages of follicle development, however, no significant change in SREBP-1 mRNA expression was observed during follicle development. Immunoreactive SREBP-2 protein levels isolated from nuclear extracts in rapid growth stages, particularly in Follicle 2, were higher than those in SWF and small yellow follicle (SYF). In contrast, SREBP-1 immunoreactive protein levels were only slightly changed over all stage of follicle development. 3-Hydroxy-3-methylglutaryl CoA reductase (HMGR) mRNA levels significantly increased in the rapid stages of follicle development, suggesting that SREBP-2 controls the biosynthesis of cholesterol in follicles. LDL receptor and LDL receptor related protein 1 mRNA also tended to increase with follicular development, however, expression of LDL receptor relative with eight ligand binding repeats (LR8) was only slightly affected by SREBP-2. Liver X receptor alpha (LXR alpha) was expressed in chicken follicles; its expression patterns corresponded with SREBP-2 gene expression. These results suggest that SREBP-2, which might be regulated by LXRalpha, is involved in the rapid growth stages of follicle development in avian species.
authors.affiliation: Graduate School of Agricultural Science, Tohoku University, Sendai, 981-8555, Japan.
authors.forename: Hyang Sook
authors.initials: HS
authors.lastname: Seol
authors.forename: Kan
authors.initials: K
authors.lastname: Sato
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Matsubara
authors.forename: Wolfgang J
authors.initials: WJ
authors.lastname: Schneider
authors.forename: Yukio
authors.initials: Y
authors.lastname: Akiba
mesh_terms: D000818:Animals; D030161:Avian Proteins / Q000235:genetics; D002645:Chickens / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics; D005260:Female; D018507:Gene Expression Regulation, Developmental; D006903:Hydroxymethylglutaryl CoA Reductases / Q000235:genetics; D008074:Lipoproteins / Q000235:genetics; D000071518:Liver X Receptors; D026503:Low Density Lipoprotein Receptor-Related Protein-1 / Q000235:genetics; D057093:Orphan Nuclear Receptors; D006080:Ovarian Follicle / Q000254:growth & development* / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics; D011973:Receptors, LDL / Q000235:genetics; D051780:Sterol Regulatory Element Binding Protein 1 / Q000235:genetics / Q000378:metabolism; D051782:Sterol Regulatory Element Binding Protein 2 / Q000235:genetics* / Q000378:metabolism
chemical_list: D030161:Avian Proteins; D004268:DNA-Binding Proteins; C116062:LR8 protein, chicken; D008074:Lipoproteins; D000071518:Liver X Receptors; D026503:Low Density Lipoprotein Receptor-Related Protein-1; D057093:Orphan Nuclear Receptors; D018160:Receptors, Cytoplasmic and Nuclear; D011973:Receptors, LDL; D051780:Sterol Regulatory Element Binding Protein 1; D051782:Sterol Regulatory Element Binding Protein 2; D006903:Hydroxymethylglutaryl CoA Reductases