Nucleic Acids Research Advance Access published online on October 9, 2009
Nucleic Acids Research, doi:10.1093/nar/gkp838
Gene Regulation, Chromatin and Epigenetics |
TMEM8 – a non-globin gene entrapped in the globin web
1Institute of Gene Biology of the Russian Academy of Sciences, Vavilov street 34/5, 119334 Moscow and 2Department of Molecular Biology, Faculty of Biology, M.V. Lomonosov Moscow State University, 119992 Moscow, Russia
*To whom correspondence should be addressed. Tel: +7095 1353092; Fax: +7(499) 1354105; Email: sergey.v.razin{at}usa.net
Received July 18, 2009. Revised September 21, 2009. Accepted September 22, 2009.
For more than 30 years it was believed that globin gene domains included only genes encoding globin chains. Here we show that in chickens, the domain of 
-globin genes also harbor the non-globin gene TMEM8. It was relocated to the vicinity of the -globin cluster due to inversion of an 
170-kb genomic fragment. Although in humans TMEM8 is preferentially expressed in resting T-lymphocytes, in chickens it acquired an erythroid-specific expression profile and is upregulated upon terminal differentiation of erythroblasts. This correlates with the presence of erythroid-specific regulatory elements in the body of chicken TMEM8, which interact with regulatory elements of the -globin genes. Surprisingly, TMEM8 is not simply recruited to the -globin gene domain active chromatin hub. An alternative chromatin hub is assembled, which includes some of the regulatory elements essential for the activation of globin gene expression. These regulatory elements should thus shuttle between two different chromatin hubs.
The authors wish it to be known that, in their opinion, the first two authors should be regarded as joint First Authors.