Genetic Recombination and the Function of RNA during Meiosis

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We have 18 cloned DNAs expressed during first meiotic prophase of lily microsporocytes by the substraction hybridization against the somatic RNAs isolated from very young anther. We are trying to understand the function of these genes. First, we have obtained complete LIM13 DNA previously missing the 5'end and concluded the basic sequences of all 18 cDNAs. Secondly, LIM15 DNA showing a high homology with E.coli RecA which is a important factor for homologous recpmbination in prokaryotes, has been localized on meiotic prophase chromosomes by using anibodies prepared against LIM15 protein synthesized in E.cili cells. LIM15 protein are found in many spots along the pairing and paired chromosome. The number of such spots are far more than the number chiasma (order of X10^3) and can be agreeable with the DNA repair spots reported earlier. It has been found that RAD52 and other RAD proteins co-localize with LIM15 and we consider this as the suggestive evidence that recombination requires than one protein.On the other hand, LIM14 gene is expressed in meiotic cells but the product has been detected in tapetal cells, tetrads and in pollen till the maturity. LIM14 protein is localized in the staarch granules of those cells but not in the starch granules in stem, leaf, root and the anther wall cells. The LIM14 protein is rich in glycine and serine contents. It has some similarity in the amino acid sequence with the reported cell wall protein. LIM14 protein has a plastid-transport signal at the N-terminal peptide, which can be useful if one trys to send a protein to the plastids or starch granules.