Identity. 45-aa pyrin-domain fragment (first two PYD helices) encoded by a processed
retrocopy of an NLRP2/NLRP7-like gene on Xp11.21. HGNC: gene with protein product
(prev. symbol NLRP2P; aliases NOD24, NALP2P, CLRX.1, POP4). UniProt PE2 (transcript level),
MANE Select ENST00000434992.1. HPA: protein not detected. PAN-GO: 0 IBA annotations.
Not an alt-ORF of another gene, so the standard folder convention applies.
Literature. PubMed search (NLRP2B OR NLRP2P OR "pyrin-only protein 4") returns only
PMID:24871464 and a 2013 review predating it (PMID:24062743, not cited). One-paper gene.
Key findings from PMID:24871464 (full text, PMC4311403):
- Locus is processed-pseudogene-like but keeps an ORF under purifying selection
PMID:24871464
- Structure: only helices 1-2 of a PYD PMID:24871464
- mRNA induced by LPS in THP-1; absent from HeLa and A293T
PMID:24871464
- Protein itself was never seen by western blot; only intracellular FLAG staining
PMID:24871464
- NF-kB: reduces TNF-induced reporter, acts at/downstream of RelA, reduces S536 phosphorylation
PMID:24871464
- TLR cytokines: overexpression lowers, siRNA knockdown in THP-1 raises TNF/IL-6
PMID:24871464
- No inflammasome inhibition (contrast with POP2)
PMID:24871464
- Cell cycle / apoptosis: HeLa overexpression, only under CHX (+TNF)
PMID:24871464
Decisions. 11 rows: 9 ACCEPT (4 location, TNF and TLR signalling, S536 phosphorylation,
two NOT rows), 2 KEEP_AS_NON_CORE (apoptosis, cell cycle). No REMOVE: every row is
experimental from a full-text paper and the claims match the data. Caveats recorded:
evidence is mostly overexpression labelled IMP; localisation is of a tagged protein in a
non-expressing line; endogenous protein never detected. No MF assigned (mechanism unknown).
No NEW: the TNF and TLR terms already cover the NF-kB effect; a general NF-kB term
(GO:0043124) raised as a question instead. Comparator: paralog PYDC2/POP2 (Q56P42) carries
the positive versions of both NOT rows (GO:0032691, GO:1900226), so the NOT rows are informative.