Pj. Good, A CONSERVED FAMILY OF ELAV-LIKE GENES IN VERTEBRATES, Proceedings of the National Academy of Sciences of the United Statesof America, 92(10), 1995, pp. 4557-4561
A large family of genes encodes proteins with RNA recognition motifs t
hat are presumed to bind RNA and to function in posttranscriptional re
gulation. Neural-specific members of this family include elav, a gene
required for correct differentiation and maintenance of neurons in Dro
sophila melanogaster, and a related gene, HuD, which is expressed in h
uman neuronal cells. I have identified genes related to elav and HuD i
n Xenopus laevis, zebrafish, and mouse that define a family of four cl
osely related vertebrate elav-like genes (elrA, elrB, elrC, and elrD)
in fish, frogs, and mammals. In addition to protein sequence conservat
ion, a segment of the 3'-untranslated sequence of elrD is also conserv
ed, implying a functional role in elrD expression. In adult frogs, elr
C and elrD are exclusively expressed in the brain, whereas elrB is exp
ressed in brain, testis, and ovary, During Xenopus development, elrC a
nd elrD RNAs are detected by late gastrula and late neurula stages, re
spectively, whereas a nervous system-specific elrB RNA species is expr
essed by early tadpole stage. Additional elrB transcripts are detected
in the ovary and early embryo, demonstrating a maternal supply of mRN
A and possibly of protein These expression patterns suggest a role for
different elav-like genes in early development and neuronal different
iation. Surprisingly, elrA is expressed in all adult tissues tested an
d at all times during development. Thus, the widely expressed elrA is
expected to have a related function in ail cells.