Isolation and characterization of two cyclin-like cDNAs from Arabidopsis.
Cyclins are key regulators of a family of protein kinases called cyclin-dependent kinases (Cdks). Specific cyclins interact with specific Cdks to regulate the different transition points in the cell cycle. Six mitotic-like cyclins have previously been reported in Arabidopsis thaliana. Using polymerase chain reaction amplified cyclin-box sequences as probes, two new cyclin cDNAs are isolated from Arabidopsis. The deduced amino acid sequences of the isolated cDNAs (Arath; CycB1;3 and Arath; CycB1;4) show the highest sequence similarity with mitotic cyclins. Arath; CycB1;3 is most homologous to the plant CycB1 group cyclins and contains a conserved motif that is typical of this group. Arath; CycB1;4, while homologous to Arath; CycB1;2, has some features that make it different from other known mitotic-like cyclins. These data suggest the presence of several distinct cyclins of CycB1 group in Arabidopsis. Analysis of expression of three members of CycB1 group (Arath; CycB1;2, Arath; CycB1;3 and Arath; CycB1;4) in different tissues by reverse transcription-polymerase chain reaction using primers corresponding to unique regions of their cDNAs shows that they are differentially expressed in different tissues.
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Department of Biology, Colorado State University, Fort Collins 80523, USA.
Reddy
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D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D017124:Conserved Sequence; D019926:Cyclin B / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D056744:Cyclin B1; D018076:DNA, Complementary / Q000302:isolation & purification; D019143:Evolution, Molecular; D008969:Molecular Sequence Data; D010802:Phylogeny; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
D019926:Cyclin B; D056744:Cyclin B1; D018076:DNA, Complementary