Lange A J, el-Maghrabi M R, Pilkis S J
Department of Physiology and Biophysics, State University of New York, Stony Brook 11794-8661.
Arch Biochem Biophys. 1991 Oct;290(1):258-63. doi: 10.1016/0003-9861(91)90617-r.
In order to ascertain whether the heart and liver forms of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase were products of two different genes or arose via alternative splicing of a single gene, the bovine liver cDNA of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase was isolated from a lambda gt10 phage library and its sequence compared with that of bovine heart cDNA. The deduced amino acid sequence of the bovine liver cDNA was also compared with the amino acid sequence of the human and rat liver phosphofructo-2-kinase/fructose-2,6-bisphosphatase enzyme. The bovine liver cDNA codes for a protein that has 81.6% amino acid identity with the bovine heart form and 97.0 and 98.3% identity with the rat and human liver forms of the enzyme, respectively. Comparison of the nucleotide sequences of the two bovine cDNAs and their deduced amino acid sequences demonstrates that while there is conservation of the active sites of liver/muscle and heart 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatases they are encoded by different genes.
为了确定6-磷酸果糖-2-激酶/果糖-2,6-二磷酸酶的心脏型和肝脏型是两个不同基因的产物还是通过单个基因的可变剪接产生，从λgt10噬菌体文库中分离出牛肝脏6-磷酸果糖-2-激酶/果糖-2,6-二磷酸酶的cDNA，并将其序列与牛心脏cDNA的序列进行比较。还将推导的牛肝脏cDNA氨基酸序列与人及大鼠肝脏磷酸果糖-2-激酶/果糖-2,6-二磷酸酶的氨基酸序列进行了比较。牛肝脏cDNA编码的一种蛋白质与牛心脏型有81.6%的氨基酸同一性，与大鼠和人类肝脏型该酶分别有97.0%和98.3%的同一性。对两种牛cDNA的核苷酸序列及其推导的氨基酸序列进行比较表明，虽然肝脏/肌肉型和心脏型6-磷酸果糖-2-激酶/果糖-2,6-二磷酸酶的活性位点保守，但它们由不同的基因编码。
