CHARACTERIZATION OF THE CELL CYCLE REGULATED GENE HG1.1

描述(改编自申请人的摘要)：监管机构 控制细胞周期进入和退出的机制似乎是 在肿瘤的发展中很重要，因为这种异常表明 明显缺乏适当的细胞生长控制。这可能是 缺乏对退出细胞周期的控制的结果，通过 肿瘤抑制基因的作用，或进入细胞周期通过 显性癌基因的作用。一种当前的细胞周期模型 规则认为，G1期代表着细胞在其中 要么在退出细胞周期之前停止增殖，要么 区分、变得停滞不前或承诺继续 另一个细胞周期。虽然一些被认为可以规范这一点的组件 已鉴定的系统(如p34cdc2、rb105、G1期细胞周期蛋白)中的许多 细节仍是个谜。最近，一种独特的人类G1期特异性 从Low的消减文库中分离到hG1.1基因 丰富的G1期转录本。该基因的转录发生在 连续细胞在G1期的一个非常窄的时间窗口 循环并从静止状态返回大气层。因此，该基因可能代表了一种 新的细胞周期调节因子，可能作为G1期的一部分参与 网关。拟议研究的总体目标是澄清以下部分 调节细胞如何确定其在G1期的反应的机制，通过 鉴定这个G1期特定转录本的作用和 它的功能与其他已知的G1期调控基因的功能相关 基因。这项研究的目的是扩大克隆 并进一步鉴定了hG1.1的生物学作用。克隆人 所采用的策略被选择用于G1期特异性表达；然而， 需要进一步的表征才能确定hG1.1在 细胞周期进程的调节。具体目标将是 确定hG1.1的高表达和低表达对正常细胞有何影响 周期进程以及这种效应是否特定于特定的细胞周期 相位。具体目标是：(1)全长克隆和测序 编码G1期特异性mRNA hG1.1的cDNA，这是人类细胞周期的一个阶段- 特定转录本，(2)表征不受调控的影响 HG1.1过表达对暂时性和稳定期细胞周期进程的影响 转染实验，以及(3)表征抑制作用的效果 反义hG1.1在细胞周期进程中的表达 寡核苷酸喂养。

DESCRIPTION (Adapted from the applicant's abstract): The regulatory mechanisms controlling entry and exit from the cell cycle appear to be important in development of neoplasia because this abnormality indicates an apparent lack of appropriate cell growth control. This may be the result of a lack of control in regulating exit from the cell cycle, through the action of tumor suppressor genes, or entry into the cell cycle through the action of the dominant oncogenes. One current model of cell cycle regulation holds that G1 phase represents a gateway during which cells either cease to proliferate before retiring from the cell cycle to differentiate, become quiescent or become committed to proceed through another cell cycle. While some of the components thought to regulate this system have been identified (eg.p34cdc2, RB105, G1 phase cyclins) many of the details remain enigmatic. Recently, a unique human G1 phase-specific cDNA (hG1.1) has been isolated from a subtractive cDNA library of lower abundance G1 phase transcripts. Transcription of this gene occurs during a very narrow window of time during G1 phase of both the continuous cell cycle and re-entry from quiescence. Therefore, this cDNA may represent a novel cell cycle regulator and may participate as part of the G1 phase gateway. The overall goal of the proposed research is to elucidate part of the mechanism regulating how a cell determines its response in G1 phase by characterizing the role of this G1 phase-specific transcript and correlating its function with those of other known G1 phase regulatory genes. The objectives of this research are designed to extend the cloning and further characterize the biological role of hG1.1. The cloning strategy employed selected for G1 phase-specific expression; however, further characterization is required to determine the role hG1.1 plays in the regulation of cell cycle progression. The specific objectives will determine what effect over and underexpression of hG1.1 have on normal cell cycle progression and if this effect is specific to a particular cell cycle phase. The specific objectives are: (1) Clone and sequence full length cDNA encoding the G1 phase-specific mRNA hG1.1, a human cell cycle phase- specific transcript, (2) Characterize the effects of unregulated overexpression of hG1.1 on cell cycle progression in transient and stable transfection assays, and (3) Characterize the effects of inhibition of hG1.1 expression on cell cycle progression by the use of antisense oligonucleotide feeding.