Receptor-Ck regulates membrane-bound 125 kDa protein having affinity for genomic sterol regulatory sequence.

The study addressed, to resolve the role of Receptor-Ck activation in the proteolytic maturation of 125 kDa (membrane bound) sterol regulatory element binding protein (SREBP), revealed that Receptor-Ck dependent signalling is not only responsible for the proteoloytic cleavage of this 125 kDa SREBP resulting in the generation of an active 47 kDa factor but also Receptor-Ck protein has high binding affinity for both 125 kDa SREBP as well as its cleaved 47 kDa product. Based upon these coupled with our earlier findings, we propose that Receptor-Ck may be regulating genes, have sterol regulatory element (SRE) in their promoter region, through the proteolytic maturation of 125 kDa SREBP into an active 47 kDa transcription factor.