Alternative splicing and expression of the mouse estrogen receptor-relatedreceptor gamma

Estrogen receptor-related receptors (ERRs) are orphan members of the nuclea r receptor superfamily, closely related to the estrogen receptor. With a PC R-based cloning strategy we have identified two cDNA isoforms from a neonat al mouse whole brain cDNA library encoding ERR gamma. We show that alternat ive splicing gives rise to different 5'-ends. The predicted peptide sequenc e of ERR gamma 2 differs from ERR gamma 1 by additional 23 N-terminal resid ues. The presence of identical isoforms in human suggests a pivotal functio n of ERR gamma in mammalia. Northern blot analysis reveals that ERR gamma i s expressed as early as day 11 of embryonic development (E11). Whole mount in situ hybridization analysis shows major expression of ERR gamma in the c entral nervous system at E12.5. in the adult mouse a 5.7 kb transcript is d etected in heart, brain, kidney, and skeletal muscle. Therefore, ERR gamma may be involved in the differentiation, as well as the maintenance of the d ifferentiated properties in the brain. (C) 2000 Academic Press.