Identification Of TCF4N Isoform In Esophageal Cell Line EC109

Alternative splicing is a process of a mRNA precursor was spliced in different combination sites form different splice mRNA variants. Study confirmed that the normal physiology, cell growth regulation,and Disease occurrence and development, are closely related with Alternative splicing. TCF4(Also called TCF7L2) belongs to TCF/LEF protein family, in the process of normal tissue development and differentiation, and receiving beta -catenin signal, initiate downstream signaling pathways, thereby promoting cell proliferation and differentiation TCF is a key nuclear transcription factor of the classical Wnt signal transduction pathway, the study of alternative splicing of TCF4 has the important practical significance.This topic design ideas as a starting from confirmed esophagealcarcinoma TCF4Nsplicing isomers, and to explore its preliminary function.RT-PCR technology was applied to amplify the specific exon of TCF4N and the product was further sequenced. The code region of TCF4N was amplified and further ligated into eukaryotic expression vector. The recombinant vector, which was verified by sequencing, was then transfected into EC109 cells to detect its roles. TCF4N splicing isoform existed in human esophageal cancer cell line, as well as esophageal tissues. Compared with that of adjacent tissues, TCF4N was downregulated in esophageal cancer tissues. TCF4N expression vector was successful constructed, which was effective expressed in EC 109 cells as detected by immuneblotting. Functional analysis showed high level expression of TCF4N led to inhibition of cell growth, cell cycle redistribution and attenuation of TCF4 transcription activity. TCF4N was an authentic expressed isoform in human esophageal cancer cells, which was relative to tumorigenesis of esophageal cancer. TCF4 as a transcriptional cofactor, which itself can not decide to open or inhibition of gene expression. Combined with other transcription activator protein determines the expression of target genes regulated by it. In the Wnt/beta -catenin signal transduction pathway, TCF4plays an important role in the occurrence and development, and the development process involved in many tumors, it may become a new target in tumor gene therapy in the future.