Abstract: 【Objective】To investigate the correlativity between the four screened ESTs and the genic male sterility, full length cDNA of the four genes were obtained, and the expression patterns of different materials and different organs were analyzed.【Method】The expression patterns of the four genes were detected by RT-PCR. Full length cDNA were cloned using the rapid-amplification of cDNA ends technique (RACE). Physical and chemical properties of proteins were analyzed with the bioinformatics softwares. RT-PCR was employed to detect expression patterns of the genes in different organs (anther, ovary, petal, sepal and leaf) and anthers from different developmental stages (tetrad stage, early- or mid-uninucleate stage, late-uninucleate stage and binucleate stage).【Result】According to the results of Blastx, the four genes were named as CaSEP1, CaPROF, CaOle e 6 and CaPCP, separately. Full length of CaSEP1 is 1 108bp, which codes 221 amino acids and contains a MADS domain and a K domain. The full length CaPROF includes 767 base pairs and 131 amino acids, which has a PROF domain. CaOle e 6 is 523 bp in full length, codes 85 amino acids with an Ole e 6 domain. Full length of CaPCP includes 563 base pairs and 66 amino acids. Amino acid sequence alignments and phylogeny reconstructions indicate that CaSEP1 is most similar to the tomato SEP1 protein and they have the closest relationship. CaPROF is more similar to profilins from tobacco and tomato than other species and shows the closest genetic distance with tomato profiling, CaOle e 6 is similar to the tomato Ole e 6 protein and they are classified into the same cluster, CaPCP shows the most similarity with tea pollen like protein and they are closest in genetic distance. RT-PCR showed that CaSEP1 expressed only in the reproductive organs of the fertile line with higher expression in anther, ovary and petal than sepal and leaf. CaPROF expressed significantly higher in anther than leaf of the fertile line, while no expression in other organs. CaOle e 6 expressed significantly higher in anther than other organs of the fertile line. CaPCP showed specific expression in anther of the fertile line. The expression of CaSEP1 increased gradually before decreasing in the binucleate stage of fertile anther, while it increased gradually in sterile anther during microspore development. The gene shows a similar expression between fertile line and sterile line at the tetrad stage of microspore development. At early- or mid-uninucleate stage and late-uninucleate stage, the gene expresses higher in fertile line. While the expression in fertile line is lower than sterile line during binucleate stage of microspore development. CaPROF, CaOle e 6 and CaPCP only express at the late stages (late-uninucleate stage and binucleate stage).【Conclusion】Analysis of sequences and expression profilings of the four genes indicates close relationships to male fertility. This study provides important information for revealing the mechanism of male sterility and regulating male fertility in pepper.

Key words: pepper , genic male sterility , expression , gene clone , sequence analysis