C-rich stability element
 | This article may be confusing or unclear to readers. (August 2008) |
The C-rich Not M, -ND stability element is a short part of a gene sequence important for the proper synthesis of globin and several other human proteins.
Differences in the stabilities of individual
ribonucleoprotein
complex at this site. Subsequently Holcik and Liebhaber identified three other highly stable eukaryotic mRNAs that assemble the alpha globin protein complex at homologous pyrimidine-rich regions within their 3'UTRs (rabbit lipoxygenase, rat tyrosine hydroxylase, and human alpha(I)-collagen).
ErEN cleavage site V -cccaacgggcccu—ccucccc—ucc/u alpha globin (HBA1 or HBA2, NM_000517.1) cccca-----cccu—cuuccccaa lipoxygenase (ALOX15, NM_001140) -ccca----gcccacuuuuccccaa alpha(I)-collagen (COL1A1, NM_000088) cucca---uccccu----ucuccaa tyroilsmochie hydroxylase (TH, NM_000360)
ycca 1–5 cccw 1–4 ucycc : consensus (Holcik and Liebhaber, 1997)
There is some debate as to the number and identity of
which?
] the complex may protect a site near the C-rich element in the alpha globin mRNA from the erythroid endonuclease (ErEN). As many of the protein components necessary for alpha globin stability complex appear to be widely expressed across species and cell types this mechanism of mRNA stabilisation is likely to be a general one. However, in the mouse the cis and trans determinants have diverged to some extent. The mouse sequence requirements are equally C and U-rich compared to the predominantly C-rich human element. Despite this shift the murine alpha globin mRNA is still as stable due to a complementary change in the specificity of the poly(C)-binding protein.
References
- J Kong and S A Liebhaber (2007). "A cell type–restricted mRNA surveillance pathway triggered by ribosome extension into the 3' untranslated region". Nature Structural & Molecular Biology. 14 (7): 670–676. PMID 17572684.