Ökaryotik canlılarda korunmuş olan Loc115098 geninin işlevsel tanımlandırılması

Loc115098 is a newly identified gene in our laboratory. The gene was firstly discoveredin an unrelated study in which the cis-acting regulatory elements of a neighboring geneNIS (Sodium-Iodide Symporter) were investigated. It is composed of 4 exons. Accordingto the computational predictions, it has rather interesting features such as having acomposition of mostly charged amino acids, carrying a nuclear localization signal andbeing well conserved throughout the eukaryotic kingdom. Our aim in this study was tounderstand the function of this new gene. Firstly we confirmed that it is expressed inseveral different tissues, later we conducted a subcellular localization study whose resultsled us to hypothesize that the function of loc115098 could be related to cell cycleregulation. According to our hypothesis we decided to utilize a lower eukaryote carryinga human homologue of loc115098 which we selected to be Aspergillus nidulans. It was avery useful model organism for our study not only because it carries a very similarhomologue of loc115098 but also it is an easily handled organism which is widely usedfor genetic studies. Firstly we compared the expression profile of loc115098 in severalcell cycle mutants of A. nidulans as well as a wild type strain, the results indicated thatthe expression of loc115098 decreases in the restrictive temperature of cell cycle mutantstrains. We also conducted subcellular localization studies in A. nidulans and the resultsindicated that it was mostly cytoplasmic and sometimes perinuclear. Our other aim was toutilize A. nidulans as a model for our knock-out experiments. We designed a knock-outsystem by the help of a sophisticated method called Double-Joint PCR. Our first attemptssupported that the knock-out of loc115098 was likely to cause lethality in the organismand therefore we improved our system to conditionally knock out the gene. Ourpreliminary results indicated that the knock out of loc115098 causes cell death and wesuspect that it could be due to a damage in one of the crucial metabolic events for cellviability such as mitosis. Our attempts to functionally characterize the function ofloc115098 are currently going on.