Oxygenated derivatives of cholesterol (oxysterols) present a remarkably diverse profile of biological activities, including effects on sphingolipid metabolism, platelet aggregation, apoptosis, and ...

Oxysterols: modulators of cholesterol metabolism and other processes.

In steroid-synthesizing cells, like the MA-10 mouse tumor Leydig cells, the peripheral-type benzodiazepine receptor (PBR) is an outer mitochondrial membrane protein involved in the regulation of cholesterol transport from the outer to the inner mitochondrial membrane, the rate-determining step in steroid biosynthesis. Expression of PBR in Escherichia coli DE3 cells, which have no PBR, no cholesterol, and do not make steroids, induced the ability to take up cholesterol in a time-dependent, temperature-sensitive, and energy- independent manner. These cells took up no other steroids tested. Addition of the high affinity PBR ligand PK 11195 to cholesterol-loaded membranes, obtained from cells transfected with PBR, resulted in the release of the uptaken cholesterol. Expression in DE3 cells of mutant PBRs demonstrated that deletions in the cytoplasmic carboxy-terminus dramatically reduced the cholesterol uptake function of PBR, although it retained full capacity to bind PK 11195. Site-directed mutagenesis in th...

Peripheral-type benzodiazepine receptor function in cholesterol transport. Identification of a putative cholesterol recognition/interaction amino acid sequence and consensus pattern.

https://www.med.upenn.edu/dreyfusslab/publications/2001FriesenMolCell1111.pdf

SMN, the Product of the Spinal Muscular Atrophy Gene, Binds Preferentially to Dimethylarginine-Containing Protein Targets

Peripheral-type benzodiazepine receptor: structure and function of a cholesterol-binding protein in steroid and bile acid biosynthesis.

Homocysteine is a sensitive marker of folate and vitamin B12 deficiency. Numerous studies have confirmed the association between folate deficiency and depression. It is not completely understood whether homocysteine is solely a marker for folate deficiency or if it may play a more direct role in the expression of mood disorders. This review describes the biochemical, neurochemical and clinical correlations of folate deficiency and hyperhomocysteinemia in relation to depression.

Virginia Tsankova

Papers

Peripheral benzodiazepine receptor ligands in rat liver mitochondria: effect on cholesterol translocation

Biochemical analysis of myelin lipids and proteins in a model of methyl donor pathway deficit: effect of S-adenosylmethionine.

Peripheral benzodiazepine receptor ligands in rat liver mitochondria: effect on 27-hydroxylation of cholesterol