※ U body introduction U body is uridine-rich small nuclear ribonucleoproteins (U snRNPs). Drosophila SMN complex proteins Gemin2, Gemin3, and Gemin5 are components of U bodies (1). And U bodies have recently been described in human cells as discrete 200-400 nm nonmembranous cytoplasmic microdomains containing uridine-rich small nuclear ribonucleoproteins U1, U2, U4/U6 and U5 (U snRNPs). U bodies may be involved in snRNP and mRNA assembly and/or transport (2). U snRNPs are assembled in the cytoplasm into U bodies, which also contain essential snRNP (splicesome) assembly factors, suggesting that U bodies are sites for assembly or storage of snRNPs before being imported into the nucleus (3).
Reference
1. Cauchi, R. J., Sanchez-Pulido, L., & Liu, J. L. (2010) Drosophila SMN complex proteins Gemin2, Gemin3, and Gemin5 are components of U bodies. Exp Cell Res, 316(14), 2354-2364. PMID: 20452345
2. Moser, J. J., & Fritzler, M. J. (2013) Relationship of other cytoplasmic ribonucleoprotein bodies (cRNPB) to GW/P bodies. Adv Exp Med Biol, 768, 213-242. PMID: 23224973
3. Liu, J. L., & Gall, J. G. (2007) U bodies are cytoplasmic structures that contain uridine-rich small nuclear ribonucleoproteins and associate with P bodies. Proc Natl Acad Sci U S A, 104(28), 11655-11659. PMID: 17595295
U body in eukaryotes (Total number, Predicted number):
1. Cauchi, R. J., Sanchez-Pulido, L., & Liu, J. L. (2010) Drosophila SMN complex proteins Gemin2, Gemin3, and Gemin5 are components of U bodies. Exp Cell Res, 316(14), 2354-2364. PMID: 20452345
2. Moser, J. J., & Fritzler, M. J. (2013) Relationship of other cytoplasmic ribonucleoprotein bodies (cRNPB) to GW/P bodies. Adv Exp Med Biol, 768, 213-242. PMID: 23224973
3. Liu, J. L., & Gall, J. G. (2007) U bodies are cytoplasmic structures that contain uridine-rich small nuclear ribonucleoproteins and associate with P bodies. Proc Natl Acad Sci U S A, 104(28), 11655-11659. PMID: 17595295
U body in eukaryotes (Total number, Predicted number):