Primary structure of alanyl-tRNA synthetase and the regulation of its mRNA levels in Bombyx mori.
cDNA clones encoding Bombyx mori alanyl-tRNA synthetase were isolated from a library in lambda gt11 using antibody, synthetic oligonucleotides, and a characterized cDNA as probes. Analysis of the sequence revealed significant homology between the B. mori and Escherichia coli alanyl-tRNA synthetases, particularly in their amino-terminal domains. Northern blot analysis indicated that the mRNA for alanyl-tRNA synthetase is 3.8 kilobase pairs in mRNA isolated from posterior silk gland, middle silk gland, and ovarian tissue. Steady-state levels of alanyl-tRNA synthetase mRNA in the posterior silk gland increased in the first 48 h of the fifth larval instar, decreasing gradually thereafter. In the middle silk gland, alanyl-tRNA synthetase mRNA peaked at 72 h of the fifth larval instar, declining to undetectable levels by 120 h. Genomic Southern blot analysis using a nick-translated cDNA probe revealed hybridization to single fragments when B. mori genomic DNA was digested with various restriction endonucleases.
Chang
P K
PK
Department of Biochemistry, University of Mississippi Medical Center, Jackson 39216-4505.
Dignam
J D
JD
D000412:Alanine-tRNA Ligase / Q000235:genetics* / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D012831:Bombyx / Q000201:enzymology / Q000235:genetics*; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D005786:Gene Expression Regulation; D015723:Gene Library; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D011061:Poly A / Q000235:genetics / Q000302:isolation & purification; D011487:Protein Conformation; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid
D015345:Oligonucleotide Probes; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D011061:Poly A; D012313:RNA; D004247:DNA; D000412:Alanine-tRNA Ligase