Factor (s) involved in transport of HBV mRNAs

已经显示，B型肝炎病毒的mRNA的转运被TAg雷克斯抑制，TAg是一种雷克斯突变体，其通过隔离细胞辅因子而主要抑制Rev/雷克斯功能。此外，我们发现hCRM 1的过表达部分恢复了HBV mRNA的转运，而不是Rev/雷克斯功能的完全恢复。这些结果表明，CRM 1类似物，而不是hCRM 1本身，参与HBV mRNA的转运。今年这项研究的目的是鉴定可能参与HBV mRNA转运的因子，特别是hCRM 1的类似物。为了克隆它，我们使用hCRM 1基因的引物，在宽松条件下以HeLa cDNA为模板进行RT-PCR。PCR产物的序列分析表明，所有的hCRM 1本身。接下来，我们使用从星形细胞瘤细胞制备的cDNA作为模板，其中Rev不能有效地起作用。结果表明，扩增产物与hCRM 1 cDNA的核苷酸序列相似性为89%，氨基酸序列相似性为97%。我们将这个新基因命名为u-CRM 1。目前，我们正在测试它是否参与HBV mRNA的转运。

It has been shown that transport of mRNAs of Hepatitis B virus is inhibited by TAgRex, a Rex mutant, which dominantly inhibits Rev/Rex functions by sequestering the cellular cofactor(s). Moreover we showed that overexpression of hCRM1 partially restored the transport of HBV mRNA in contrast to the complete restoration of Rev/Rex functions. These results suggested that CRM1 analog, but not hCRM1 itself, is involved in the transport of HBV mRNAs. The purpose of the study this year is to identify the factor(s), particularly an analog of hCRM1, which may be involved in transport of HBV mRNAs. To clone it, we performed RT-PCR using primers of the hCRM1 genes with HeLa cDNA as template under the relaxed conditions. Sequence analysis of the PCR products indicated that all were hCRM1 itself. Next, we used cDNA prepared from astrocytoma cells, where Rev does not work efficiently, as template. It has been revealed that the amplified product had the sequence which has 89% similar to the hCRM1 cDNA at nucleotide level and 97% similar in amino acid sequence. We named this new gene as u-CRM1. Currently we are testing it to be involved in transport of HBV mRNAs.