A novel zinc finger-containing RNA-binding protein conserved from fruitflies to humans.
The Drosophila lark gene encodes an essential RNA-binding protein of the RNA recognition motif (RRM) class that is required during embryonic development. Genetic analysis demonstrates that it also functions as a molecular element of a circadian clock output pathway, mediating the temporal regulation of adult emergence in the fruitfly. We now report the molecular characterization of a human gene with significant similarity to lark. Based on fluorescence in situ hybridization and radiation hybrid mapping, the human gene has been localized to chromosome region 11q13; it is closely linked to several identified genes including the locus of Bardet-Biedl syndrome type 1. The lark-homologous human gene expresses a single 1.8-kb size class of mRNA in most or all tissues including brain. Additional database searches have identified a mouse counterpart that is virtually identical to the human protein. Similar to lark protein, both mammalian proteins contain two copies of the RRM-type consensus RNA-binding motif. Unlike most RRM family members, however, the Drosophila and mammalian proteins also contain a retroviral-type (RT) zinc finger that is situated 43 residues C-terminal to the second RRM element. Within a 184-residue segment spanning the RRM elements and the RT zinc finger, the human and mouse proteins are 61% similar to the Drosophila lark sequence. These common sequence features and comparisons among a large collection of RRM proteins suggest that the human and mouse proteins represent homologues of Drosophila lark.
Jackson
F R
FR
Department of Neuroscience, Tufts University School of Medicine, Boston, Massachusetts 02111, USA. rjackson@opal.tufts.edu
Banfi
S
S
Guffanti
A
A
Rossi
E
E
D000328:Adult; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics; D016384:Consensus Sequence; D017124:Conserved Sequence; D018076:DNA, Complementary / Q000235:genetics; D004330:Drosophila / Q000235:genetics*; D029721:Drosophila Proteins; D019143:Evolution, Molecular; D015870:Gene Expression; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D019476:Insect Proteins / Q000235:genetics; D051379:Mice; D008969:Molecular Sequence Data; D016601:RNA-Binding Proteins / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D016335:Zinc Fingers / Q000235:genetics*
D018076:DNA, Complementary; D029721:Drosophila Proteins; D019476:Insect Proteins; C105214:Lark protein, Drosophila; D016601:RNA-Binding Proteins