Mobility of nucleoside transporter of human erythrocytes differs greatly when loaded with different nucleosides.
Mobility of nucleoside transporter of human erythrocytes differs greatly when loaded with different nucleosides.
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人红细胞核苷转运蛋白在负载不同核苷时的迁移率差异很大。
DOI：
10.1016/0005-2736(90)90405-d
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发表时间：
1990
期刊：
影响因子：
--
通讯作者：
Woffendin,C
中科院分区：
文献类型：
--
作者：
Plagemann,PG;Aran,JM;Wohlhueter,RM;Woffendin,C
采用快速动力学技术测定了2-氯腺苷、2 ' -脱氧腺苷、3 ' -脱氧腺苷、胞苷和2 ' -脱氧胞苷在平衡交换和零反式条件下在人红细胞中的跨膜平衡时间。通过对7种浓度的数据拟合适当的积分速率方程，计算了转运的动力学参数，并与先前在可比实验条件下测定的人红细胞尿苷、腺苷、胸腺嘧啶和甲霉素B转运的动力学参数进行了比较。所有核苷的输运均符合简单载体模型，且方向对称。平衡交换的Michaelis-Menten常数（K ee）从2-氯腺苷的22 μM到胞苷的约4 mM不等，最大速度（V ee）也有类似的差异，因此所有核苷的一级速率常数（V ee/K ee）相似。2′-脱氧腺苷运输的动力学参数与腺苷运输的动力学参数相似，而3′-OH基团的缺乏大大降低了3t′-脱氧腺苷（虫草素）对载体的亲和力，2′，3′-二脱氧核苷的运输效率低于2′和3t′-脱氧核苷的1%。因此，2 ‘和3 ’ -OH基团在核苷转运中起重要作用。载嘧啶核苷载体的迁移率（由V - ee反映）是空载体的5 - 10倍，而载腺苷或载2 ' -脱氧腺苷载体的迁移率与空载体的迁移率大致相等。在载体上装载2-氯腺苷或3 ' -脱氧腺苷实际上降低了它的流动性。因此，负载载体和空载体的差异迁移率随核苷底物的不同而有很大的不同。负载载体的迁移率和kee随着核苷底物脂溶性的降低而增加，但这种关系是复杂的。
Time courses of transmembrane equilibration of 2-chloroadenosine, 2′-deoxyadenosine, 3′-deoxyadenosine, cytidine and 2′-deoxycytidine were measured by rapid kinetic techniques in human erythrocytes under equilibrium exchange and zero-trans conditions. The kinetic parameters for transport were computed by fitting appropriate integrated rate equations to the data pooled for seven concentrations and compared to the kinetic parameters for uridine, adenosine, thymidine and formycin B transport determined previously for human erythrocytes under comparable experimental conditions. The transport of all nucleosides conformed to the simple carrier model and was directionally symmetric. The Michaelis-Menten constants for equilibrium exchange (K ee) ranged from 22 μM for 2-chloroadenosine to about 4 mM for cytidine and the maximum velocities (V ee) differed in a similar manner, so that the first-order rate constants (V ee/K ee) were similar for all nucleosides. The kinetic parameters for 2′-deoxyadenosine transport were similar to those for adenosine transport, whereas the lack of the 3′-OH group greatly reduced the affinity of 3t́-deoxyadenosine (cordycepin) for the carrier, 2′, 3′-Dideoxynucleosides were transported< 1% as efficiently as 2′-and 3t́-deoxynucleosides. Thus, the 2′-and 3′-OH groups play an important role in nucleoside transport. The mobility of the carrier when loaded with pyrimidine nucleosides (reflected by V ee was 5–10-times greater than that of the empty carrier, whereas the mobility of th adenosine-loaded or 2′-deoxyadenosine-loaded carrier was about equal to that of the empty carrier. Loading the carrier with 2-chloroadenosine or 3′-deoxyadenosine actually decreased its mobility. Thus, the differential mobility of the loaded and empty carrier differs greatly with the nucleoside substrate. The mobility of the loaded carrier as well as K ee increased with a decrease in lipid solubility of the nucleoside substrate, but the relationship was complex.
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使用福霉素 B 作为测量哺乳动物细胞中促进核苷转运的通用底物。
DOI：
10.1016/0167-4889(89)90177-8
发表时间：
1989
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
Plagemann,PG;Woffendin,C
通讯作者：
Woffendin,C
第 16 章测量悬浮动物细胞转运的快速混合技术：在 Novikpff 大鼠肝癌细胞中核苷转运的应用
影响因子：
--
作者：
R. Wohlhueter;R. Marz;J. Graff;P. Plagemann
通讯作者：
P. Plagemann
渗透性核苷对人红细胞尿苷流出的反式刺激和反式抑制。
DOI：
10.1042/bj2330295
发表时间：
1986
期刊：
The Biochemical journal
影响因子：
--
作者：
S. Jarvis
通讯作者：
S. Jarvis
影响因子：
4.8
作者：
C. Cass;A. Paterson
通讯作者：
A. Paterson
影响因子：
5.6
作者：
PLAGEMANN, PG
通讯作者：
PLAGEMANN, PG