PAXIP1-ASSOCIATED GLUTAMATE-RICH PROTEIN 1; PAGR1

Alternative titles; symbols

• PTIP-ASSOCIATED 1 PROTEIN; PA1
• CHROMOSOME 16 OPEN READING FRAME 53; C16ORF53

HGNC Approved Gene Symbol: PAGR1

Cytogenetic location: 16p11.2 Genomic coordinates (GRCh38): 16:29,816,151-29,822,488 (from NCBI)

▼ Description
PAGR1 is a component of a Set1-like multiprotein histone methyltransferase complex (Cho et al., 2007).

▼ Cloning and Expression
By affinity purification of PTIP (PAXIP1; 608254)-associated proteins in a HeLa cell line expressing mouse Ptip, followed by mass spectrometry, Cho et al. (2007) identified PAGR1, which they designated PA1. The predicted 254-amino acid protein shares 87% sequence identity with the mouse ortholog. When ectopically expressed in HeLa cells, PA1 localized to the nucleus.

▼ Gene Function
Using mass spectrometry and protein purification, Cho et al. (2007) identified PA1 as part of a larger complex of PTIP-associated proteins including ASH2L (604782), RBBP5 (600697), WDR5 (609012), NCOA6 (605299), MLL3 (606833), MLL4 (606834), and DPY30 (612032). The protein complex is a Set1-like histone methyltransferase complex that displays histone H3 lysine-4 (H3K4) methyltransferase activity. GST pull-down assays showed that PA1 interacts directly with PTIP but not with ASH2L, RBBP5, WDR5, or NCOA6. PA1 requires PTIP for interaction with the rest of the complex.

▼ Mapping
Gross (2014) mapped the PAGR1 gene to chromosome 16p11.2 based on an alignment of the PAGR1 sequence (GenBank BC003640) with the genomic sequence (GRCh37).