Activity, expression and function of a second Drosophila protein kinase A catalytic subunit gene.
The DC2 gene was isolated previously on the basis of sequence similarity to DC0, the major Drosophila protein kinase A (PKA) catalytic subunit gene. We show here that the 67-kD Drosophila DC2 protein behaves as a PKA catalytic subunit in vitro. DC2 is transcribed in mesodermal anlagen of early embryos. This expression depends on dorsal but on neither twist nor snail activity. DC2 transcriptional fusions mimic this embryonic expression and are also expressed in subsets of cells in the optic lamina, wing disc and leg discs of third instar larvae. A saturation screen of a small deficiency interval containing DC2 for recessive lethal mutations yielded no DC2 alleles. We therefore isolated new deficiencies to generate deficiency trans-heterozygotes that lacked DC2 activity. These animals were viable and fertile. The absence of DC2 did not affect the viability or phenotype of imaginal disc cells lacking DC0 activity or embryonic hatching of animals with reduced DC0 activity. Furthermore, transgenes expressing DC2 from a DC0 promoter did not efficiently rescue a variety of DC0 mutant phenotypes. These observations indicate that DC2 is not an essential gene and is unlikely to be functionally redundant with DC0, which has multiple unique functions during development.
Meléndez
A
A
Department of Biological Sciences, Columbia University, New York, New York 10027, USA.
Li
W
W
Kalderon
D
D
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002384:Catalysis; D017868:Cyclic AMP-Dependent Protein Kinases / Q000235:genetics* / Q000378:metabolism; D018076:DNA, Complementary; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004330:Drosophila / Q000196:embryology / Q000201:enzymology / Q000235:genetics*; D029721:Drosophila Proteins; D018507:Gene Expression Regulation, Developmental; D017930:Genes, Reporter; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D009899:Optic Lobe, Nonmammalian / Q000196:embryology / Q000201:enzymology; D010641:Phenotype; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors; D051879:Twist-Related Protein 1
D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors; C497753:Twi protein, Drosophila; D051879:Twist-Related Protein 1; C062236:dl protein, Drosophila; C000604451:sna protein, Drosophila; D017868:Cyclic AMP-Dependent Protein Kinases