MTMR9 notes

2026-09-08 paired review

Selected accession A0A9L0T3C1; ordinary UniProt record is TrEMBL and cites genome sequencing/submission rather than a gene-specific functional experiment. Human evidence is summarized in the paired human investigation. Sequence comparison records the exact target gaps and transfer limits. The targeted Europe PMC search found no decisive gene-specific horse functional assay warranting a separate horse Edison investigation; general omics/association hits were not counted as mechanistic validation.

MTMR9 lacks intrinsic phosphatase catalysis but dimerizes with active MTMR6, MTMR7 and MTMR8. Human MTMR6/MTMR9 and MTMR8/MTMR9 studies directly measure altered catalytic rates, substrate preferences, cellular phosphoinositide levels and downstream phenotypes. The 2009 study also finds increased partner abundance consistent with stabilization. The 2012 study distinguishes the MTMR6/R9 anti-apoptotic role from MTMR8/R9 inhibition of autophagy. These are positive reasons to retain regulatory and process participation claims. The molecular-function distinction between generic phosphatase regulation and binding specifically to a protein phosphatase still needs attention because the experimentally studied partners are lipid phosphatases.

Sources: PMID:19038970(https://pubmed.ncbi.nlm.nih.gov/19038970/), PMID:22647598(https://pubmed.ncbi.nlm.nih.gov/22647598/).