Article

Male gametic cell-specific gene expression in flowering plants, Proc. Natl. Acad. Sci. USA 96, 2554-2558

Plant Molecular Biology and Biotechnology Laboratory, Institute of Land and Food Resources, University of Melbourne, Parkville, Victoria 3052, Australia.
Proceedings of the National Academy of Sciences (Impact Factor: 9.67). 04/1999; 96(5):2554-8. DOI: 10.1073/pnas.96.5.2554
Source: PubMed

ABSTRACT

The role of the male gamete-the sperm cell-in the process of fertilization is to recognize, adhere to, and fuse with the female gamete. These highly specialized functions are expected to be controlled by activation of a unique set of genes. However, male gametic cells traditionally have been regarded as transcriptionally quiescent because of highly condensed chromatin and a very reduced amount of cytoplasm. Here, we provide evidence for male gamete-specific gene expression in flowering plants. We identified and characterized a gene, LGC1, which was shown to be expressed exclusively in the male gametic cells. The gene product of LGC1 was localized at the surface of male gametic cells, suggesting a possible role in sperm-egg interactions. These findings represent an important step toward defining the molecular mechanisms of male gamete development and the cellular processes involved in fertilization of flowering plants.

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    • "Several different patterns of gene expression in the male germ lineage have been elucidated. Expression 330 of LGC1 is restricted to generative cell and sperm cells (Xu et al., 1999). When LGC1 promoter was 331 truncated, male germline specificity was lost and expression became constitutive (Singh et al., 2003). "
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    • "These epigenetic factors continue to be a major theme in modern work as well. Promoter analysis has revealed that there are male germlineselective promoters that are activated in the generative and sperm cells (Xu et al., 1999; Okada et al., 2005a). Whereas most promoters are positively controlled, there is also evidence for a complex silencing element that controls male germline expression through a repressor that is expressed in all but male germ cells (Haerizadeh et al., 2006). "
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    • "). In recent years, several cDNA libraries from mature anthers of tomato, pollen of Brassica campestris, and generative cells of lily were constructed, and library screenings with northern blot analysis led to the isolation of male-gamete-specific genes, such as LAT52 and LGC1 (Twell et al., 1989; Theerakulpisut et al., 1991; Xu et al., 1998, 1999). Since large scale EST (expressed sequence tag) sequencing was not applied in these studies, the information obtained about gene expression in the male gametes was still relatively limited. "
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