Characterization and functional analysis of a pollen-specific gene st901 in Solanum tuberosum.
A pollen-specific gene, sb401, which was isolated from a cDNA library of in vitro geminated pollen of the diploid potato species Solanum berthaultii, belongs to the class of genes expressed late during pollen development. Using sb401 as a probe, a pollen-specific gene st901 was isolated from the genomic library of a potato species Solanum tuberosum cv. Desiree. Sequencing and RT-PCR analysis showed that the st901 genomic gene is 2,889 bp long, contains three exons and two introns, and encodes a putative polypeptide of 217 residues. The predicted protein sequence contains four imperfect repeated motifs of V-V-E-K-K-N/E-E; the core sequence of the repeats (K-K-N/E-E) resembles a microtubule-binding domain of the microtubule-associated protein MAP1B from mouse. The examination of a promoter-reporter construct in transgenic potato plants revealed that the st901 is expressed exclusively in mature pollen grains, which is consistent with the results of Northern blot and RT-PCR. For analysis of the function of st901, transgenic plants harboring antisense copies of st901 cDNA driven by a native st901 promoter were generated. Suppression of st901 gene in potato resulted in aberrant pollen at maturation and pollen viability of transgenic plants ranged from 4.4 to 14.8%, while that of control plants were more than 90%. These results strongly suggest that st901 has an essential role in pollen development.
Zhao
Yan
Y
State Key Laboratory for Agricultural Biotechnology, College of Biological Sciences, China Agricultural University, No. 2 Yuanmingyuan West Road, 100094, Beijing, People's Republic of China.
Zhao
Qian
Q
Ao
Guangming
G
Yu
Jingjuan
J
D000595:Amino Acid Sequence; D016384:Consensus Sequence / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D020868:Gene Silencing; D017343:Genes, Plant / Q000235:genetics*; D018745:Genome, Plant / Q000235:genetics; D008969:Molecular Sequence Data; D010641:Phenotype; D010940:Plant Proteins / Q000737:chemistry; D030821:Plants, Genetically Modified; D011058:Pollen / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D011401:Promoter Regions, Genetic / Q000235:genetics; D016372:RNA, Antisense / Q000235:genetics; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics; D015183:Restriction Mapping; D017422:Sequence Analysis, DNA; D011198:Solanum tuberosum / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D013489:Suppression, Genetic
D018744:DNA, Plant; D010940:Plant Proteins; D016372:RNA, Antisense