Biological complexity: more mitochondrial controls found (Introduction)

by David Turell , Friday, April 17, 2020, 22:21 (1681 days ago) @ David Turell

"16 'short open reading frame-encoded peptides' (SEPs) whose genetic code is translated in the nucleus, but which are then imported into mitochondria, the power-generating structures of cells":

https://www.sciencedaily.com/releases/2020/04/200416135841.htm

"SEPs have been fascinating the scientific community for several years now, as they represent a mini-proteome that has never been explored; a repository of new gene functions," said Dr Ho. "But there haven't been systematic studies to validate their functions and biological relevance. We found that the mitochondria are a hotspot for their functions, for reasons we don't completely yet understand."

The scientists singled out one of the 16 mitochondrial SEPs they discovered for further analysis. Knocking out the gene that codes for the SEP, which they named BRAWNIN, in zebrafish led to extreme growth retardation and lactic acid accumulation in cells. Further tests revealed that BRAWNIN was essential for the assembly of a group of molecules in the mitochondria called respiratory chain complex III. This molecular complex is essential for all life forms that use oxygen for energy generation, according to Dr Ho.

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Dr Ho also noted there are 15 more mitochondrial SEPs to investigate. "We are actively looking for collaborators who are interested in studying them," she added.

Comment: the fact that these are integrated with the cell nucleus indicates the degree of complex design that has cells doing their jobs. Designer required.