Goulding M, Ralph R K
Mol Cell Biochem. 1985 May;67(1):31-8. doi: 10.1007/BF00220983.
A substantial increase in cyclic AMP-dependent protein kinase activity occurred in nuclei of PY815 mastocytoma cells during G1 phase growth arrest by DB cyclic AMP and the increased nuclear protein kinase was accompanied by changes in nuclear protein phosphorylation. However, there was no obligatory association between the rise in nuclear cyclic AMP-dependent protein kinase in G1 phase and growth arrest because nuclear cyclic AMP-dependent protein kinase also increased during G1 phase in cycling PY815 cells synchronized with amethopterin. These observations suggest that maintenance of high cyclic AMP levels during G1 phase may cause growth arrest by activating a cyclic AMP-dependent protein kinase that normally increases in PY815 cell nuclei during G1 phase.
在DB环磷酸腺苷（DB cyclic AMP）诱导的PY815肥大细胞瘤细胞G1期生长停滞期间，细胞核中环磷酸腺苷依赖性蛋白激酶活性显著增加，并且增加的核蛋白激酶伴随着核蛋白磷酸化的变化。然而，G1期核中环磷酸腺苷依赖性蛋白激酶的升高与生长停滞之间并没有必然联系，因为在与氨甲蝶呤同步化的循环PY815细胞的G1期，核中环磷酸腺苷依赖性蛋白激酶也会增加。这些观察结果表明，在G1期维持高环磷酸腺苷水平可能通过激活一种在PY815细胞核中通常在G1期增加的环磷酸腺苷依赖性蛋白激酶来导致生长停滞。
