Function of RRM domains of Drosophila melanogaster ELAV: Rnp1 mutations and rrm domain replacements with ELAV family proteins and SXL.
Members of the ELAV family of proteins contain three RNA recognition motifs (RRMs), which are highly conserved. ELAV, a Drosophila melanogaster member of this family, provides a vital function and exhibits a predominantly nuclear localization. To investigate if the RNA-binding property of each of the ELAV RRMs is required for ELAV's in vivo function, amino acid residues critical in RNA binding for each RRM were individually mutated. A stringent genetic complementation test revealed that when the mutant protein was the sole source of ELAV, RNA-binding ability of each RRM was essential to ELAV function. To assess the degree to which each domain was specific for ELAV function and which domains perhaps performed a function common to related ELAV proteins, we substituted an ELAV RRM with the corresponding RRM from RBP9, the D. melanogaster protein most homologous to ELAV; HuD, a human ELAV family protein; and SXL, which, although evolutionarily related, is not an ELAV family member. This analysis revealed that RRM3 replacements were fully functional, but RRM1 and RRM2 replacements were largely nonfunctional. Under less stringent conditions RRM1 and RRM2 replacements from SXL and RRM1 replacement from RBP9 were able to provide supplemental function in the presence of a mutant hypomorphic ELAV protein.
Department of Biology and Center for Complex Systems, Brandeis University, Waltham, Massachusetts 02454, USA.
M J
MJ
Lisbin
M
M
Gordon
Y M
YM
Yannoni
K
K
White
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000596:Amino Acids / Q000737:chemistry; D000818:Animals; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000737:chemistry / Q000235:genetics*; D051959:ELAV Proteins; D005816:Genetic Complementation Test; D015151:Immunoblotting; D007150:Immunohistochemistry; D007301:Insect Hormones / Q000235:genetics*; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000235:genetics; D010957:Plasmids / Q000235:genetics; D016133:Polymerase Chain Reaction; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012313:RNA / Q000378:metabolism*; D016601:RNA-Binding Proteins; D012261:Ribonucleoproteins / Q000737:chemistry / Q000235:genetics* / Q000502:physiology; D012262:Ribonucleoside Diphosphate Reductase; D012269:Ribosomal Proteins / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D019076:Transgenes; D025521:Tumor Suppressor Proteins
D000596:Amino Acids; D029721:Drosophila Proteins; D051959:ELAV Proteins; D007301:Insect Hormones; D009419:Nerve Tissue Proteins; D016601:RNA-Binding Proteins; C082384:RNP1 protein, S cerevisiae; C117851:RRM1 protein, Trypanosoma brucei; C079911:Rbp9 protein, Drosophila; D012261:Ribonucleoproteins; D012269:Ribosomal Proteins; D029701:Saccharomyces cerevisiae Proteins; C067777:Sxl protein, Drosophila; D025521:Tumor Suppressor Proteins; D012313:RNA; C475286:RRM1 protein, human; D012262:Ribonucleoside Diphosphate Reductase