Identification and mapping of genes expressed in pollen and during pollen-pistil interaction in maize

Identification and mapping of genes expressed in pollen and during pollen-pistil interaction in maize The subject of my Ph.D. work was the study of the genomic organization of genes involved in pollen development and function. The first topic was the construction of a functional pollen map of genetic factors controlling the above mentioned processes in maize. A complete panel of oat maize addition lines was exploited to map 1000 maize pollen EST contigs. This large scale mapping revealed that pollen genes are distributed among the ten maize chromosomes and provided evidence for duplication of many genes. Then a positional cloning approach was performed, in order to isolate and characterize Gametophyte Factor 1, a gene responsible of cross-sterility in maize. This gene was previously mapped on chromosome 4, bin 4.02. In order to generate a high-resolution map of the region, we generated a large segregating population of 3000 individuals, phenotypically and molecularly characterized. We placed additional molecular markers obtained from maize genomic and BAC-ends sequences derived from clones sequencing and we created a high-resolution map of the Ga1 region, delimiting a genetic region of 1.03 cM encompassing Ga1. The analysis of the public physical map has led to the identification of a single BAC contig. At the same time, the exploitation of rice-maize synteny has been pursued to identify a region on rice chromosome 11, syntenic to the maize interval flanking Ga1.