Characterization of pollen-specific genes in alfalfa (Medicago sativa L.).

摘要

The objective of the research presented in this thesis was to characterize pollen-specific genes in alfalfa. The working hypothesis was that pollen development in alfalfa involves pollen-specific genes and the 5;The promoter regions of the three genes contain no common sequence even though these three genes show the same expression pattern. In transgenic tobacco and alfalfa plants containing PO149 or PO22 promoter-GUS fusion constructs, no GUS activity was detected in any tissues except pollen. In pollen the GUS activity was detectable shortly after microspore mitosis, maximum in mature pollen and continued into pollen tube growth. Both constructs showed transient expression in pollen grains from canola (Brassica napus), wheat (Triticum aestivum) and barley (Hordeum vulgare), following particle bombardment.