Genetic analysis of the Drosophila 63F early puff. Characterization of mutations in E63-1 and maggie, a putative Tom22.
The 63F early puff in the larval salivary gland polytene chromosomes contains the divergently transcribed E63-1 and E63-2 ecdysone-inducible genes. E63-1 encodes a member of the EF-hand family of Ca(2+)-binding proteins, while E63-2 has no apparent open reading frame. To understand the functions of the E63 genes, we have determined the temporal and spatial patterns of E63-1 protein expression, as well as undertaken a genetic analysis of the 63F puff. We show that E63-1 is expressed in many embryonic and larval tissues, but the third-instar larval salivary gland is the only tissue where increases in protein levels correlate with increases in ecdysone titer. Furthermore, the subcellular distribution of E63-1 protein changes dynamically in the salivary glands at the onset of metamorphosis. E63-1 and E63-2 null mutations, however, have no effect on development or fertility. We have characterized 40 kb of the 63F region, defined as the interval between Ubi-p and E63-2, and have identified three lethal complementation groups that correspond to the dSc-2, ida, and mge genes. We show that mge mutations lead to first-instar larval lethality and that Mge protein is similar to the Tom22 mitochondrial import proteins of fungi, suggesting that it has a role in mitochondrial function.
Vaskova
M
M
Department of Molecular Pharmacology and Biological Chemistry, Northwestern University, Chicago, Illinois 60611-3093, USA.
Bentley
A M
AM
Marshall
S
S
Reid
P
P
Thummel
C S
CS
Andres
A J
AJ
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism; D002872:Chromosome Deletion; D002874:Chromosome Mapping; D002875:Chromosomes / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D004330:Drosophila / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029721:Drosophila Proteins; D005260:Female; D018507:Gene Expression Regulation, Developmental; D017344:Genes, Insect; D005816:Genetic Complementation Test; D017403:In Situ Hybridization; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism; D007814:Larva / Q000254:growth & development; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D026901:Membrane Transport Proteins; D008928:Mitochondria / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D011956:Receptors, Cell Surface; D017386:Sequence Homology, Amino Acid
D002135:Calcium-Binding Proteins; D018076:DNA, Complementary; D029721:Drosophila Proteins; C095576:Eip63F-1 protein, Drosophila; D019476:Insect Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D011956:Receptors, Cell Surface