title: Arabidopsis DOK1 encodes a functional dolichol kinase involved in reproduction.
abstract: Dolichol phosphate (Dol-P) serves as a carrier of complex polysaccharides during protein glycosylation. Dol-P is synthesized by the phosphorylation of dolichol or the monodephosphorylation of dolichol pyrophosphate (Dol-PP); however, the enzymes that catalyze these reactions remain unidentified in Arabidopsis thaliana. We performed a genome-wide search for cytidylyltransferase motif-containing proteins in Arabidopsis, and found that At3g45040 encodes a protein homologous with Sec59p, a dolichol kinase (DOK) in Saccharomyces cerevisiae. At3g45040, designated AtDOK1, complemented defects in the growth and N-linked glycosylation of the S. cerevisiae sec59 mutant, suggesting that AtDOK1 encodes a functional DOK. To characterize the physiological roles of AtDOK1 in planta, we isolated two independent lines of T-DNA-tagged AtDOK1 mutants, dok1-1 and dok1-2. The heterozygous plants showed developmental defects in male and female gametophytes, including an aberrant pollen structure, low pollen viability, and short siliques. Additionally, the mutations had incomplete penetrance. These results suggest that AtDOK1 is a functional DOK required for reproductive processes in Arabidopsis.
authors.affiliation: Academia Sinica, Institute of Plant and Microbial Biology, No. 128 Sec. 2 Academia Rd., Nankang Taipei, 11529, Taiwan; Molecular and Biological Agricultural Sciences Program, Academia Sinica, Taiwan International Graduate Program, No. 128 Sec. 2 Academia Rd., Nankang, Taipei, 11529, Taiwan; Biotechnology Center, National Chung-Hsing University, 250 Kuo-Kuang Rd., Taichung, 402, Taiwan; Department of Applied Science and Engineering, Muroran Institute of Technology, 27-1 Mizumoto-cho, Muroran, Hokkaido, 050-8585, Japan.
authors.forename: Kazue
authors.initials: K
authors.lastname: Kanehara
authors.forename: Yueh
authors.initials: Y
authors.lastname: Cho
authors.forename: Ying-Chen
authors.initials: YC
authors.lastname: Lin
authors.forename: Chia-En
authors.initials: CE
authors.lastname: Chen
authors.forename: Chao-Yuan
authors.initials: CY
authors.lastname: Yu
authors.forename: Yuki
authors.initials: Y
authors.lastname: Nakamura
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics; D004288:Dolichol Phosphates / Q000378:metabolism; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics / Q000378:metabolism*; D012098:Reproduction / Q000502:physiology
chemical_list: D004288:Dolichol Phosphates; C026406:dolichol pyrophosphate; D017853:Phosphotransferases (Alcohol Group Acceptor); C020087:dolichol kinase
keywords: Arabidopsis thaliana; N-linked glycosylation; cytidylyltransferase; dolichol kinase; protein glycosylation; reproduction