In Vitro Transcription and Translation of Lipoprotein Lipase

LPL is regulated post-transcriptionally in response to several hormones. Post-translational regulation occurs in response to feeding (1 ,2 ). Glycosylation of LPL at the first N-linked glycosylation site is essential for catalytic activity and secretion (3 ). A number of studies have demonstrated the importance of glycosylation using inhibitors of glycosylation, and inhibitors of glycoprotein transfer from the RER to the Golgi (4 ,5 ). Additional insight can be obtained from studies of the cld/cld mouse, which expresses large amounts of inactive LPL and HL protein due to a recessive mutation not involving the structural genes for LPL or HL (6 ,7 ). Thus, the cld mutation appears to either interfere with LPL and HL oligosaccharide processing, or with transport from the RER to the Golgi.