SREBP sterol-responsive element binding

SREBP Sterol response element binding protein... 

Abbreviations FASN, fatty acid synthase ACC, acetyl-CoA-carboxylase ACL, ATP-citrate lyase NADPH, nicotinamide adenine dinucleotide phosphate MAT, malonyl acetyl transferases KS, ketoacyl synthase KR, p-ketoacyl reductase DH, p-hydroxyacyl dehydratase ER, enoyl reductase TE, thioesterase ACP, acyl carrier protein VLCFA, very long chain fatty acids ELOVL, elongation of very long chain fatty acids SCDl, stearoyl-CoA desaturase-1 AMPK, AMP-activated kinase ME, malic enzyme FASKOL, liver-specific deletion of FAS PPARa, Peroxisome Proliferator-Activating Receptor alpha HMG-CoA, 3-hydroxy-3-methyl-glutaryl-CoA SREBP, sterol response element binding protein SIP, site-one protease S2P, site-two... 

The concentration of LDL-cholesteroi in the blood is a function of its rate of production and rate of removal from the bloixistream. Diet influences LDL-cho-lesterol by changing its rate of removal or clearance, according to the following scenario. Let us briefly return to the topics of proteins and DMA, A transcription factor called sterol response element binding protein (SREbP) binds to a stretch of DNA called the sterol response element. The sterol response element has the structure CACCCCAC. In discussing any sequence of DNA, it is conventional to... 

Fig. 6. Coordinated transcriptional regulation of fatty acid desaturases and elongases in mammals. PUFA, polyunsaturated fatty acids +, stimulation inhibition LXR, liver X receptor RXR retinoid X receptor SREBP, sterol regulatory element binding protein ChREBP, carbohydrate response element binding protein Mix, Max-like receptor PPAR-ot, peroxisome proliferator activated receptor alpha LXRE, liver X receptor response element SRE, sterol response element ChoRE, carbohydrate response element PPRE, peroxisome proliferator response element. (See color plate section, plate no. 6.)...

Sterol-response element-binding proteins (SREBPs) are transcription factors that coor-dinately increase the synthesis of fatty acids and cholesterol (Chapters 6, 7, and 14). The transcriptionally active forms of SREBPs are generated from precursor proteins by a sterol-dependent proteolytic cleavage [8]. Several studies have indicated that an increased production of transcriptionally active SREBPs stimulates VLDL secretion. 

Sterol responsive element binding protein (SREBP)... 

Members of a family of nuclear transcription factors called sterol regulatory element-binding proteins (SREBP) are responsible for the regulation of these cholesterol feedback mechanisms. SREBP are able to activate a number of genes encoding for proteins involved in the homeostasis of cholesterol and other lipids, including the LDL receptor gene itself. 

Fatty acid synthase is transcriptionally regulated by upstream stimulatory factor and sterol regulatory element binding protein Ic (SREBP-lc), in response to feeding/insulin. 

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