Nuclear lamins are involved in many cellular functions due to their ability to bind numerous partners including chromatin and transcription factors, and affect their properties. Dunnigan type familial partial lipodystrophy (FPLD2; OMIM#151660) is caused in most cases by the A-type lamin R482W mutation. We report here that the R482W mutation affects the regulatory activity of sterol response ele...

Introduction: Orexin A and adiponectin are involved in controlling metabolism energy distribution the body during lactation. Lactation is a process with high demand for lipid synthesis. Peroxisome proliferator-activated receptor gamma (PPARγ) sterol regulatory element-binding protein 1 (SREBP1c) two transcription factors that regulate milk The goal of this study was to assess effects mammary ad...

The transcription factor sterol regulatory-element-binding protein-1c (SREBP-1c) plays a major role in the effect of insulin on the transcription of hepatic genes such as glucokinase and fatty acid synthase. We show here in cultured rat hepatocytes that insulin, through activation of the phosphatidylinositol 3-kinase pathway increases the abundance of the precursor form of SREBP-1c in endoplasm...

SREBP1 (Sterol regulatory element binding protein 1), transcription factor that regulates hundreds of genes involved in lipid metabolism and adipocyte differentiation, is a direct partner of A-type lamins. We show that i) in vitro, the tail regions of prelamin A, lamin A and lamin C bind a polypeptide of SREBP1 and ii) within cells, interactions between wild-type A-type lamins and SREBP1 occur ...

The amount of cholesterol in animal cell membranes is tightly regulated to maintain proper cell function. Experiments performed over the past several years have shown that this regulation occurs in large part through transcription factors that control the expression of genes involved in cholesterol metabolism. The ‘sterol regulatory element binding proteins’ (SREBPs) are a class of transcriptio...

To elucidate the role of hormone-sensitive lipase (HSL) in diet-induced obesity, HSL-deficient (HSL-/-) and wild-type mice were fed normal chow or high-fat diets. HSL-/- mice were resistant to diet-induced obesity showing higher core body temperatures. Weight and triacylglycerol contents were decreased in white adipose tissue (WAT) but increased in both brown adipose tissue (BAT) and liver of H...

Lanosterol 14alpha-demethylase (CYP51) produces follicular fluid meiosis-activating sterol (FF-MAS), which is converted further to testis meiosis-activating sterol (T-MAS). MAS are intermediates in the cholesterol biosynthetic pathway, with the ability to trigger resumption of oocyte meiosis in vitro. In contrast to the liver, where pre- and post-MAS genes are upregulated coordinately at the le...

We have previously demonstrated that growth of embryonic chick atrial cells in medium supplemented with lipoprotein-depleted serum (LPDS) resulted in a coordinate increase in the expression of genes involved in the parasympathetic response of the heart (the M2 muscarinic receptor; the alpha-subunit of the heterotrimeric G protein, Galpha(i2); and the inward rectifying K+ channel protein, GIRK1)...

Sterol regulatory element-binding proteins (SREBPs) are transcription factors central to the regulation of lipid metabolism. The SREBPs are synthesized as precursor proteins that require proteolytic processing to become transcriptionally active. Whereas the regulation of SREBP-1a and -2 cleavage by cellular sterol content is well defined, much less is known about the regulation of SREBP-1c, the...