Autophagy Related Protein 5 (ATG5)

ASP shares 26% amino acid sequence identity with the S. cerevisiae APG5 gene product, which is involved in yeast autophagy. ASP contains a high number of acidic residues, a potential glycosylation site, and potential casein kinase II , protein kinase C, and tyrosine kinase sites. While the molecular mass of recombinant ASP expressed in bacteria is 32 kD, Western blot analysis of recombinant ASP expressed in mammalian cells detected 32- and 45-kD polypeptides; the authors stated that the difference in molecular masses between ASP expressed in bacteria and in mammalian cells is likely due to posttranslational modifications. Northern blot analysis detected approximately equal levels of ASP mRNA in all human tissues examined. The ASP gene is expressed as major 3.3- and 1.8-kb transcripts.