Cell molecular biology - Essay Example

array expression data for the cyclin genes of Tetrhymena thermophila were collected in an attempt to assess the role of individual cyclin gene products in the complex process of conjugation that characterizes the cell division cycle of this unicellular eukaryotic microorganism. The expression data were obtained from genomic databases and also from reverse transcriptase-polymerase chain reactions (RT-PCR) performed to explore the cyclic expression patterns of the cyclin mRNAs during the cell cycle of T.

thermophila. The results of this analysis indicated that most of the 23 identified cyclin genes in this microorganism are transcriptionally activated at specific points during the cell cycle. The combined assessment of expression patterns and comparative sequence analysis with studies that detail the sequence of cellular events that characterizes the process of conjugation were used to generate a hypothesis about the putative functions of each of the cyclin genes of T. thermophila in the unique series of meiotic and meitotic cell divisions that characterizes the process of conjugation.

The process of cell division in the ciliated protozoans involves a complex pattern of meiotic and mitotic cell divisions as well as major nuclear restructuring events that comprise a mode of cell division that involves mechanisms of genetic exchange that characterize the unique pattern of sexual reproduction in this primitive eukaryotic microorganism that is called conjugation. This process is initiated in response to stressful environmental conditions. The initial event involves the pairing of two cells of different mating types (I-IV) followed by meiosis and the exchange of the haploid nuclei produced during meiotic cell division.

Subsequently, the nucleus of the zygote in each cell engages in several rounds of mitotic cell division. The end result is the production of two nuclei with each cell: a transcriptionally silent micronucleus and a transcriptionally active