Johnston L S, Keller K L, Keller J M
Biochim Biophys Acta. 1979 Feb 19;583(1):81-94. doi: 10.1016/0304-4165(79)90312-x.
Three major pools of heparan sulfate have been isolated from cultures of Swiss mouse 3T3 and SV40-transformed 3T3 cells: cell-surface, medium, and intracellular heparan sulfates. The cell-surface heparan sulfate is a high molecular weight proteoglycan which is partially degraded by pronase. Before pronase treatment, it has a peak molecular weight (as estimated by gel filtration) of approx. 7.2 . 10(5) in contrast to only 2.4 . 10(5) after pronase treatment. The medium heparan sulfate appears to be similar in structure to the cell-surface heparan sulfate, since they coelute on Bio-Gel A-15m and DEAE-cellulose, and are both proteoglycans. In contrast, the intracellular heparan sulfate has a low molecular weight (6.0 . 10(3)) and has little if any attached protein. Both the medium and intracellular heparan sulfate exhibit the transformation-associated change in structure reported earlier for cell-surface heparan sulfate (Underhill, C.B. and Keller, J.M. )1975) Biochem. Biophys. Res. Commun. 63, 448--454). This transformation-associated change, detected by DEAE-cellulose chromatography is not the result of changes in either molecular weight or protein core. Cellulose acetate electrophoresis of the cell-surface heparan sulfate at pH 1 suggests that the transformation-associated change in structure is due to a difference in sulfate content. Both types of heparan sulfate are produced in mixed cultures of 3T3 and SV3T3 cells, indicating that neither serum factors in the culture medium nor secreted cell products are responsible for the transformation-associated change in heparan sulfate structure. The presented data are discussed with respect to the postulated role of heparan sulfate in cell social behavior.
已从瑞士小鼠3T3细胞和SV40转化的3T3细胞培养物中分离出三种主要的硫酸乙酰肝素池：细胞表面、培养基和细胞内硫酸乙酰肝素。细胞表面硫酸乙酰肝素是一种高分子量蛋白聚糖，可被链霉蛋白酶部分降解。在链霉蛋白酶处理之前，其峰值分子量（通过凝胶过滤估计）约为7.2×10⁵，而链霉蛋白酶处理后仅为2.4×10⁵。培养基硫酸乙酰肝素的结构似乎与细胞表面硫酸乙酰肝素相似，因为它们在Bio-Gel A-15m和DEAE-纤维素上共洗脱，并且都是蛋白聚糖。相比之下，细胞内硫酸乙酰肝素分子量较低（6.0×10³），几乎没有或没有附着蛋白。培养基和细胞内硫酸乙酰肝素都表现出先前报道的细胞表面硫酸乙酰肝素的与转化相关的结构变化（Underhill，C.B.和Keller，J.M.（1975年）《生物化学与生物物理研究通讯》63，448 - 454）。通过DEAE-纤维素色谱检测到的这种与转化相关结构变化不是分子量或蛋白核心变化的结果。在pH 1条件下对细胞表面硫酸乙酰肝素进行醋酸纤维素电泳表明，与转化相关的结构变化是由于硫酸含量的差异。两种类型的硫酸乙酰肝素都在3T3和SV3T3细胞的混合培养物中产生，这表明培养基中的血清因子或分泌的细胞产物都不是硫酸乙酰肝素结构中与转化相关变化的原因。本文就硫酸乙酰肝素在细胞社会行为中的假定作用对所呈现的数据进行了讨论。
