Difference between revisions of "Part:BBa K2429023"

Latest revision as of 14:27, 24 October 2017

phEF1a L. shahii Cas13a

This part includes the Leptotrichia shahii Cas13a protein coding region downstream of the human elongation factor 1a (hEF1a) promoter, which is a low level constitutive promoter. This final expression vector produces a CRISPR protein known as Cas13a, which binds and cuts mRNA. Upon recognition of the mRNA, this protein exhibits "promiscuous" ribonuclease activity, not only cutting at base pairs along the targeted RNA molecule, but other nearby RNA molecules as well.

Typically, during the process of alternative splicing in eukaryotic cells, specific RNA binding proteins will bind to sequences or motifs on a pre-mRNA strand and eventually come together to form a spliceosome protein. This resulting protein will cleave the mRNA strand to exclude portions of the pre-mRNA (called introns) and the remaining sequences in the mature mRNA are known as exons.

Our team used this protein in an attempt to control what exons would be included in an mRNA transcript by targeting the motifs in an intron, thus blocking splicing factors from binding and retaining an exon. Furthermore, our team tested variations of this protein (e.g. catalytically deactivated, additional domains) to see whether such variations would affect the splicing capabilities. This specific variation of the protein is catalytically active in bacteria; however, since we used it in mammalian cells, the protein's endonuclease activity isn't expected to be seen. Additionally, the focus is on the protein's binding and blocking ability rather than the catalytic activity.

Sequence and Features