Analysis of highly expressed genes in the late zygotene to pachytene stages of meiotic prophase I in david lily

Plant meiotic prophase I is a complex process involving the late zygotene and pachytene stages, crucial for both completing synapsis and recombination. Using David lily (Lilium davidii var. Willmottiae) as research material, we performed suppressive subtractive hybridization to construct expessed sequence tag (EST) library of anthers at various stages of development by the pollen mother cells. From this library, we identified 34 genes with significantly enhanced expression during the late zygotene to pachytene stages. The cDNA fragment sequences were compared with data in GenBank by BLASTN and BLASTX, and 18 unique ESTs were shown to exhibit significant homology to the data in GenBank. They were classified into eight different groups: metabolism, protein modification, signal transduction, etc. Through the study of classification and functions of these highly expressed genes during the late zygotene to pachytene stages, we obtained much information about the complex biological progress of meiotic prophase I, especially during chromosome synapsis and recombination.