Rat transcobalamin: cloning and regulation of mRNA expression.
Rat transcobalamin: cloning and regulation of mRNA expression.
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大鼠转钴胺素：mRNA 表达的克隆和调节。
DOI：
10.1113/jphysiol.2003.058727
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
Seetharam,Bellur
中科院分区：
文献类型：
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作者：
Kalra,Seema;Seetharam,Shakuntla;Yammani,RaghunathaR;Seetharam,Bellur
转钴胺素（Transcobalamin， TC）已被克隆并用于研究其在大鼠中的基因表达。TC mRNA在成年大鼠组织中分布广泛，但水平不同（肾>肝>肺>卵黄囊>肠>心>脑>脾>肌肉）。空肠和回肠的TC mRNA水平是十二指肠的4倍。在出生后发育过程中，回肠TC mRNA水平从第4天到第12天下降了4倍，但在第12天到第24天增加了5倍。相比之下，TC mRNA水平从第4天到第12天增加了2.5倍，然后在第24天下降了2倍。成年大鼠肾上腺切除术导致回肠TC mRNA水平下降4倍，口服胃内因子（IF）复合[57Co]Cbl后，回肠粘膜TC - [57Co]钴胺素（Cbl）复合物形成减少50%。可的松治疗逆转了回肠的这些变化。与回肠相比，肾上腺切除大鼠在可的松治疗前后肾脏TC mRNA水平无明显改变。综上所述，本研究为大鼠出生后发育过程中肾脏和肠道TC基因表达的调控提供了证据，可的松选择性调节回肠而非肾脏TC mRNA水平。
Transcobalamin (TC) has been cloned and used for studying its gene expression in the rat. TC mRNA is distributed widely in adult rat tissues, but at different levels (kidney > liver > lung > yolk sac > intestine > heart > brain > spleen > muscle). TC mRNA levels were 4‐fold higher in the jejunum and ileum compared to its levels in the duodenum. During postnatal development, TC mRNA levels in the ileum declined 4‐fold from day 4 to day 12, but increased by 5‐fold between days 12 and 24. In contrast, TC mRNA levels increased by 2.5‐fold in the kidney from day 4 to day 12 and then declined by 2‐fold by day 24. Adrenalectomy of adult rats resulted in a 4‐fold decline in ileal levels of TC mRNA and a 50% decline in the ileal mucosal formation of the TC‐[57Co] cobalamin (Cbl) complex following oral administration of [57Co]Cbl complexed to gastric intrinsic factor (IF). Cortisone treatment reversed these changes noted in the ileum. In contrast to ileum, kidney TC mRNA levels were not altered significantly in adrenalectomized rats before and after cortisone treatment. Taken together, this study has provided evidence for the regulation of TC gene expression in the rat kidney and intestine during their postnatal development, and cortisone selectively regulates ileal but not kidney TC mRNA levels.