內吞作用 (Endocytosis) 在調控物質進入細胞以及調控下游訊息傳遞的過程中扮演重要的腳色。此外在細胞膜上具有大量的醣蛋白 (proteoglycan) 以及其他物質也都參予在細胞內吞作用中，特別是醣肝素(heparan sulfate proteoglycans) 在近幾年的研究中廣泛的被探討其在內吞作用中所扮演的功能。肝癌延生生長因子 (hepatoma-derived growth factor) 中的 HATH (homologous to the amino terminus of HDGF) 區塊可與細胞膜上的醣肝素及受體結合進入細胞，不過目前研究對於其細胞內吞作用仍然不清楚。我利用單一胺基酸突變的 HATHK96A 蛋白其與醣肝素結合但不與受體結合的特性來與 HATH 區塊蛋白做比較，經由實驗發現HATH區塊經由與受體結合可誘導短期且快速的進入細胞，且的確經由受體結合與醣肝素結合所走的路徑是不一樣的，以及探討了HATH 區塊與受體結合在細胞移動 (cell migration) 機制中所扮演的可能腳色。

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