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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Exons, Humans, Macrophages, Polymorphism, Single Nucleotide, RNA, Scavenger Receptors, Class B, Transcription, Genetic.
user
Is a synonymous variant in scavenger receptor , class B , type I gene associated with lower SR-BI protein expression and function? Context: A synonymous variant within scavenger receptor class B type I gene (SCARB1), exon 8 rs5888, has been associated with altered lipid levels and cardiovascular risk in humans. The objective was to determine if rs5888 decreased SR-BI protein expression and function in vitro. SR-BI RNA secondary structure, turnover, polysomal distribution and protein expression were examined in COS cells transfected with wild-type or rs5888-SR-BI plasmids by selective 2'-hydroxyl acylation and primer extension assays, actinomycin D inhibition, polysomal profiling, and western blotting. SR-BI function in murine macrophages stably expressing wild-type or rs5888-SR-BI was assessed by measuring the specific cell association of (125)I,(3)H-cholesteryl ester (CE) radiolabeled HDL. Rs5888 changed RNA secondary structure and led to marked differences in the polysomal profiles compared with wild-type transcript (p<0.02). As compared to wild-type cells, COS cells expressing rs5888 had significantly lower SR-BI protein expression (p<0.04), but no difference in total RNA transcript levels. There were no differences in SR-BI RNA turnover in murine macrophages, whereas specific cell association of (125)I (p<0.0001) or (3)H-CE (p<0.00001) was significantly lower in rs5888 cells.
assistant
The rs5888 variant affected SR-BI RNA secondary structure, protein translation, and was significantly associated with reduced SR-BI protein expression and function in vitro. Final Decision: yes