Rubin A L, Rice R H
Dana Laboratory of Toxicology, Harvard School of Public Health, Boston, Massachusetts 02115.
In Vitro Cell Dev Biol. 1988 Sep;24(9):857-61. doi: 10.1007/BF02623894.
The sensitivity to calcium of the human squamous carcinoma cell line, SCC-13, was demonstrated and characterized. Cultures grown to confluence in the presence of 0.2 to 2 mM calcium had approximately 10-fold higher levels of particulate transglutaminase activity and envelope competence than those grown in low calcium (0.025 to 0.05 mM) medium. Raising the calcium from 0.025 to 1.8 mM induced expression of this enzyme and of competence over the course of a week. Conversely, for cultures grown to confluence in 1.8 mM calcium, subsequent reduction of calcium to 0.025 mM resulted in a substantial decline in transglutaminase over a similar time period. Immunoprecipitable transglutaminase was clearly identifiable in cultures grown in 1.8 mM calcium-containing medium but not in those grown in low calcium medium or in the presence of retinoic acid, suggestive of regulation at the level of mRNA accumulation or translation rather than posttranslational modification.
人类鳞状癌细胞系SCC - 13对钙的敏感性得到了证实和表征。在0.2至2 mM钙存在的情况下生长至汇合的培养物，其颗粒转谷氨酰胺酶活性和包膜能力水平比在低钙（0.025至0.05 mM）培养基中生长的培养物高出约10倍。在一周的时间内，将钙浓度从0.025 mM提高到1.8 mM可诱导该酶的表达和能力。相反，对于在1.8 mM钙中生长至汇合的培养物，随后将钙浓度降低至0.025 mM会导致在相似时间段内转谷氨酰胺酶大幅下降。在含有1.8 mM钙的培养基中生长的培养物中可清楚识别出免疫沉淀的转谷氨酰胺酶，但在低钙培养基中或存在视黄酸的情况下生长的培养物中则无法识别，这表明是在mRNA积累或翻译水平而非翻译后修饰水平上进行调节。
