Phenotype Analysis Of Deletion Mutant And The Genetic Transformation Of Maize Specific Gene STK1

Pollens are male gamete of higher plants. Normal germination and rapid growth of pollen, which relate to cell recognition and signal transduction, are the key to plants fertilization. STK1 was obtained by our laboratory in the earlier stage which is a maize pollen-specific gene. The research preliminarily conducts genetic transformation and the test of pollen viability to clarify the expression period of STK1 gene and the factors that affects pollen viability, which establishes foundation for further study that STK1 impacts pollen development. The results are as follows:(1) The statistics of pollen viability from stkl mutant plants and wild-type plants are conducted by three staining ways (TTC staining, KI-I2 staining and acetic acid and carmine staining), meanwhile the capacity of pollen tube growth is tested by aniline blue staining. The result showed that acetic acid and carmine staining is the most suitable method for the determination of pollen viability. Pollen viability of the mutant and wild-type remain stable during the observation period. The average pollen viability of McC is around at 90% while that of stkl is at 45%. The elongation rate of pollen tube from McC is substantially double of that from stkl.(2) Paraffin sections of pollen in each period from the mutant plants stkl and the wild-type plant are respectively observed by transmission microscope. It showed that anther tapetum of wild-type is completely degraded during the late stage of pollen development; however anther tapetum of the mutant is degradated in advance during the middle and later stage of pollen development. According to the result, it can speculate that the abnormal change of tapetum is main reason to cause the decline of mutant pollen activity.(3) The expression vector pCAMBIA1301-pSTK1 is constructed and then it is imported to maize germinating embryo through the Agrobacterium-mediated genetic transformation technique to obtain the To Generation transformed plants. Only mature anthers and mature pollen of transgenic plants have revealed GUS signal through GUS histochemical detection while other parts have not appeared it. Thus it gets the preliminary verification that specific gene STK1 expresses in late stage of pollen development.