PMCHL2 notes (Q9BQD1, Putative pro-MCH-like protein 2)
2026-10-04 Tier 3 over-annotation audit (claude-code)
Does the product exist?
- UniProt: PE5 (Uncertain); CAUTION "Could be the product of a pseudogene". Tissue: testis, not brain.
- HGNC (REST, fetched 2026-10-04): "pro-melanin concentrating hormone like 2 (pseudogene)", locus_type
pseudogene, 5q13.2, Entrez 5370.
- Origin: duplication of a ~92 kb segment containing PMCHL1 from 5p14 to 5q13 in the hominid lineage PMID:11181993; PMID:19068116.
- Truncation: 5'-truncated version of PMCH, like PMCHL1 PMID:11070051.
- Expression: not transcribed in brain PMID:11070051; [PMID:9729295: brain antisense product "derived from the 5p (pMCHL1), not the 5q (pMCHL2) locus"]. Testis only PMID:19068116.
- Protein: Schmieder 2008 antiserum to the VMCH-p8 N-terminal epitope detected nothing in human adult testis, and nothing in HEK293 cells transfected with ORF1-bearing PMCHL1/2 sequences PMID:19068116. Note: the PMCHL2 N-terminus is KTKKK rather than KPKKK, so the epitope may differ slightly; the paper does not say whether its antiserum recognises the PMCHL2 variant. Treat protein absence for PMCHL2 as likely but slightly less directly shown than for PMCHL1.
- Q9BQD1 2-86 aligns to PMCH 81-165 (83.5% identity); PMCH 1-80 incl. signal peptide absent.
- MCH-like segment: M150T, R160Q, P161R; Cys retained. NEI-like: I132T, amidated I143 retained.
Propagation routes
- IBA GO:0031777, GO:0032227: PANTHER PTN002636265 (IBD taxon:117571 Euteleostomi, seed RGD:3358 rat Pmch); PMCHL2 in PTHR12091:SF1 with PMCHL1.
- IEA GO:0030354, GO:0007268: InterPro2GO IPR005456. GO:0007165, GO:0045202: GOC inter-ontology inference.
- (No NAS extracellular row, unlike PMCHL1.)
Decision
All 6 rows REMOVE. No core function.