Alternative titles; symbols
HGNC Approved Gene Symbol: ENDOU
Cytogenetic location: 12q13.11 Genomic coordinates (GRCh38) : 12:47,709,734-47,725,490 (from NCBI)
Placental protein-11 was initially identified as a protein associated with normal human placenta and with various malignant neoplasms of breast, ovary, testis, and stomach (see Grundmann et al., 1990). Using a polyclonal antibody against PP11, Grundmann et al. (1990) isolated a full-length PP11 cDNA from a human placenta cDNA library. The cDNA encodes a 42-kD soluble protein of 369 amino acids, including an N-terminal hydrophobic region of 18 amino acids typical of secretory proteins.
Grundmann et al. (1990) found that recombinant PP11 protein expressed in E. coli displayed diisopropyl fluorophosphate (DPF)-inhibitable amidolytic activity, suggesting function as a serine protease, although categorization of the protein as an esterase could not be ruled out. Western blot also revealed an inactive 45-kD precursor protein in PP11-transformed E. coli.
Laneve et al. (2008) found that bacterially expressed human PP11 bound RNA and cleaved single-stranded RNA in a Mn(2+)-dependent manner at uridylates to produce molecules with 2-prime,3-prime-cyclic phosphate ends. Structural and mutation analyses identified potential active-site residues. Laneve et al. (2008) concluded that PP11 is a ribonuclease and lacks protease activity.
Poe et al. (2014) used mice lacking Cd22 (107266) or mice expressing hen egg lysozyme stimulated with autoantigen to observe activation-induced cell death (AICD). They identified the RNA-binding protein Endou as a major regulator of B-cell survival in both models. Disruption of Endou prevented AICD and normalized Myc (190080) expression. Poe et al. (2014) concluded that ENDOU is a critical regulator of an RNA-dependent pathway controlling peripheral B-cell survival and antigen responsiveness that may contribute to peripheral B-cell tolerance.
Renzi et al. (2006) reported the 3-dimensional structure of XendoU, the well-conserved frog homolog of PP11, at 2.2-angstrom resolution. XendoU encodes an endoribonuclease that processes intron-encoded small nucleolar RNAs and has homology with NendoU, an enzyme necessary for maturation of the coronavirus that causes severe acute respiratory syndrome (SARS). Renzi et al. (2006) found that XendoU contains a unique fold, and they identified its active site.
Gross (2014) mapped the ENDOU gene to chromosome 12q13.11 based on an alignment of the ENDOU sequence (GenBank BC069715) with the genomic sequence (GRCh37).
Gross, M. B. Personal Communication. Baltimore, Md. 2/24/2014.
Grundmann, U., Romisch, J., Siebold, B., Bohn, H., Amann, E. Cloning and expression of a cDNA encoding human placental protein 11, a putative serine protease with diagnostic significance as a tumor marker. DNA Cell Biol. 9: 243-250, 1990. [PubMed: 2350438] [Full Text: https://doi.org/10.1089/dna.1990.9.243]
Laneve, P., Gioia, U., Ragno, R., Altieri, F., Di Franco, C., Santini, T., Arceci, M., Bozzoni, I., Caffarelli, E. The tumor marker human placental protein 11 is an endoribonuclease. J. Biol. Chem. 283: 34712-34719, 2008. [PubMed: 18936097] [Full Text: https://doi.org/10.1074/jbc.M805759200]
Poe, J. C., Kountikov, E. I., Lykken, J. M., Natarajan, A., Marchuk, D. A., Tedder, T. F. EndoU is a novel regulator of AICD during peripheral B cell selection. J. Exp. Med. 211: 57-69, 2014. [PubMed: 24344237] [Full Text: https://doi.org/10.1084/jem.20130648]
Renzi, F., Caffarelli, E., Laneve, P., Bozzoni, I., Brunori, M., Vallone, B. The structure of the endoribonuclease XendoU: from small nucleolar RNA processing to severe acute respiratory syndrome coronavirus replication. Proc. Nat. Acad. Sci. 103: 12365-12370, 2006. [PubMed: 16895992] [Full Text: https://doi.org/10.1073/pnas.0602426103]