Study On Homozygous Mutant Of Arabidopsis Thaliana AT2G17350

Bioinformatics research showed that AT2G17350 gene are found in many plants, and the protein sequence is highly conserved in plants, but the function is unknown. Arabidopsis AT2G17350 mutant for the purchase is heterozygous mutant (Heterzygous mutant, HT), selfing offspring in the soil planting found no homozygous mutant (Homozygous mutant, HM), but AT2G17350 homozygous mutant were found under the sterile culture condition. Research shows that A T2G17350 gene deletion affects the growth of plant leaf, root and hypocotyl, in order to study the mechanism of AT2G17350 gene affects plant growth and development, this experiment analyze digital gene expression profiling for AT2G17350 homozygous mutants and the wild type (Wild-type, WT)from Arabidopsis thaliana, knowed the differential expression gene mainly due to the biological function and the main biochemical metabolism pathway and signal transduction pathways involved in the AT2G17350 homozygous mutants.The main research contents and results were as follows:1. Reaerch showed that AT2G17350 homozygous mutant could not grow in the soil, only in the sterile cluture medium, and the seeding on the medium is deformity and dysplasia. Detection of AT2G17350 gene transcription by RT-PCR, the reaults showed that AT2G17350 gene was detected in Wild-type, it was not detected in AT2G17350 homozygous mutant, that showed abnormal plantlets was caused by the deletion of AT2G17350 gene.2. Observation of seedling growth and phenotype from wild-type and AT2G17350 homozygous mutant on 10 days,20 days,35 days. The 10 days, the leaves of wild type were round, leaf color was dark green, smooth edge, the leaves of AT2G17350 homozygous mutant were slender or incomplete shape, leaf color was pale, pale green with white spots or stripes, the blade edge uneven, root length and hypocotyl length were shorter than wild-type, extremely significant difference. The 20 days, AT2G17350 homozygous mutant plants and petiole were shorter compared with wild-type. The 35 days, wild-type plants were blossom while AT2G17350 homozygous mutant cannot bear fruit. So, AT2G17350 gene deletion affects seedling growth and development process, especially in leaf, root and hypocotyl growth.3. In order to study the reason of the lack of AT2G17350 homozygous mutant, the experiment results were as follows:a. The detection of pollen activity by Alexander dyeing method and observed the surface structure of the pollen by scanning electron microscope, the results show that the pollen activity and surface structure have no significant difference between WT and HT, So AT2G17350 gene deletion did not affect pollen development. b. Self crosses of AT2G17350 heterozygous mutant and reciprocal crosses of wild-type and AT2G17350 heterozygous mutant, self crosses of AT2G17350 heterozygous mutant results was about WT:HT:HM= 1:1.83:0.73, reciprocal crosses of wild-type results was WT:HT=1:1, conform to Mendelian’s law of inheritance, So the AT2G17350 gene deletion did not affect the female gametophyte development and the transfer ability of male and female gametes. c. Statistics of silique length, abortion rate of ovule, seed germination rate and seed phenotype from WT and HT, results show that all have no significant difference, So the AT2G17350 gene deletion did not affect the development of female gametophyte and the zygote. d. Statistics of seed germination rate, the results show that seed germination rate have no significant difference between WT and HT, so the AT2G17350 gene was not involved in the process of seed germination.4. Digital gene expression profile analysis showed there are 1968 differentially expressed genes(DEGs) in AT2G17350 homozygous mutant compared with wild type, including the raising DEGs were 1353, the falling DEGs were 615. Gene Ontology enrichment analysis showed that these DEGs were involved in 44 GO term, the cellular component were divided into 11, molecular function were 12, biological process were 21. In cellular component classification, DEGs were significant enrichment in organelle fraction, in molecular function classification, DEGs were significant enrichment in binding and catalysis molecular structure, in biological process classification, DEGs were significant enrichment in response to stress and stimulation approach. Results show that the AT2G17350 gene may be a key gene involved in cell structure, may be associated with protein binding and catalytic function, may be involved in stress and stimulation pathway.5. KEGG Pathway enrichment analysis showed DEGs were were enriched with 12 metabolic pathways, DEGs in ribosomal pathways were all raised, DEGs in photosynthesis pathways and photosynthesis-antenna protein pathway were all falling. Results suggested that AT2G17350 gene may be related to protein synthesis and transport, may be involved in photosynthesis and photosynthesis-antenna protein pathway, the leaves color of AT2G173A50 homozygous mutant were shallow than wild type, further confirmed that the AT2G17350 gene is involved in the photosynthesis pathway.