L63, the Drosophila PFTAIRE, interacts with two novel proteins unrelated to cyclins.
L63 encodes a CDK-like protein homologous to the mammalian PFTAIRE. We showed previously that L63 provides a CDK-related function critical to development (Dev. Biol. 221 (2000) 23). We present here the first biochemical characterization of L63 kinase. In addition, we describe two novel Drosophila proteins, PIF-1 and PIF-2 (for PFTAIRE Interacting Factor-1 and -2), identified in a two-hybrid screen for their ability to interact with the amino-terminal region of L63. The full-length PIF-1 cDNA shows an unusual dicistronic organization. PIF-1A and PIF-1B (the L63 interactor) predicted proteins are expressed in vivo, and show a distinct expression profile during development. Interaction between L63 and PIF-1B was confirmed in vitro and in vivo. The role of this interaction remains to be demonstrated, but our data suggest that PIF-1B might serve as a regulator of L63.
Rascle
Anne
A
Departments of Biochemistry and Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA. anne.rascle@dnax.org
Stowers
R Steven
RS
Garza
Dan
D
Lepesant
Jean-Antoine
JA
Hogness
David S
DS
D000595:Amino Acid Sequence; D000818:Animals; D015152:Blotting, Northern; D015153:Blotting, Western; D003001:Cloning, Molecular; D018844:Cyclin-Dependent Kinases / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D003545:Cysteine / Q000737:chemistry; D018076:DNA, Complementary / Q000378:metabolism; D004330:Drosophila; D029721:Drosophila Proteins / Q000235:genetics / Q000502:physiology*; D005091:Exons; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D008957:Models, Genetic; D008969:Molecular Sequence Data; D011233:Precipitin Tests; D011485:Protein Binding; D014176:Protein Biosynthesis; D020033:Protein Isoforms; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000378:metabolism; D014158:Transcription, Genetic; D020798:Two-Hybrid System Techniques
D018076:DNA, Complementary; D029721:Drosophila Proteins; D020033:Protein Isoforms; D012333:RNA, Messenger; D018844:Cyclin-Dependent Kinases; C408322:Eip63E protein, Drosophila; D003545:Cysteine