Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2021

Erindi/veggspjald / Talk/poster V52

A region of ATG7 evolved in vertebrates and might account for a new function

Höfundar / Authors: Valgerður Jakobína Hjaltalín, Margrét Helga Ögmundsdóttir, Arnar Pálsson

Starfsvettvangur / Affiliations: Háskóli Íslands, Líf- og læknavísindadeild, Sturlugötu 8

Kynnir / Presenter: Valgerður Jakobína Hjaltalín

Autophagy is a highly conserved degradation pathway important for maintaining homeostasis in eukaryotic cells. The E1-like enzyme ATG7 belongs to a group of ATG proteins which mediate the autophagy process. Studies on the essential autophagy protein ATG7 have indicated a novel function of the protein in mammals or vertebrates. We have described a region of ATG7 that emerged early in vertebrates. The region is situated within the adenylation domain of the protein, which is the most conserved domain of E1 enzymes. A comparative analysis revealed that ATG7 is unique in this respect, among the E1 enzyme family members where this domain has generally remained conserved from yeast to humans. This vertebrate specific region evolved rapidly in the lancelet and cartilaginous fish but seems to have stabilized in modern vertebrates. Interestingly, the region contains two sites which have been linked to cancer in humans. A site-by-site analysis of the region revealed that both of those sites are under significant natural selection only in the mammalian clade. These results indicate that this region could account for a new function of the protein in vertebrates and moreover, establish a link between the region and cancer in humans.