Lowe W L, Schaffner A E, Roberts C T, LeRoith D
Diabetes Branch, National Institute of Diabetes, Digestive and Kidney Diseases, Bethesda, Maryland 20892.
Mol Endocrinol. 1987 Feb;1(2):181-7. doi: 10.1210/mend-1-2-181.
Developmental regulation of somatostatin (SRIF) gene expression was studied in five regions of rat brain and in rat stomach. Total RNA was isolated from hypothalamus, cortex, brainstem, cerebellum, and olfactory bulb, as well as stomach at eight stages of development from prenatal day 16 to postnatal day 82. Hybridization of a 32P-labeled rat SRIF cDNA probe to Northern blots of total RNA from the above tissues during development demonstrated a single hybridizing band approximately 670 base pairs in length. When SRIF mRNA levels from each stage of development were quantified and normalized by the amount of poly (A)+ RNA present at that stage of development, a unique pattern of SRIF gene expression was seen in each region. In brainstem and cerebellum, SRIF mRNA levels peaked early in development between prenatal day 21 and postnatal day 8 and then declined until postnatal day 82. Hypothalamus and cortex, on the other hand, showed a progressive increase during development with peak levels occurring between postnatal days 13 and 82. In contrast, stomach and olfactory bulb showed SRIF mRNA levels which were low during early development and which rose late in development (postnatal days 13 to 82). Marked differences in the amount of SRIF mRNA within each region were present as well. These data suggest that there is differential expression of the SRIF gene in different regions of the brain and in the stomach during development. Further study of this phenomenon may provide insight into the in vivo control of SRIF gene expression and the role of SRIF in the developing brain.
研究了生长抑素（SRIF）基因表达在大鼠脑的五个区域和大鼠胃中的发育调控情况。从产前第16天到产后第82天的八个发育阶段，分别从下丘脑、皮层、脑干、小脑、嗅球以及胃中分离出总RNA。在发育过程中，用32P标记的大鼠SRIF cDNA探针与上述组织的总RNA进行Northern杂交，结果显示有一条大约670个碱基对长的单一杂交带。当对每个发育阶段的SRIF mRNA水平进行定量，并根据该发育阶段存在的聚腺苷酸加尾RNA（poly (A)+ RNA）量进行标准化时，在每个区域都观察到了独特的SRIF基因表达模式。在脑干和小脑中，SRIF mRNA水平在产前第21天到产后第8天的发育早期达到峰值，然后下降直至产后第82天。另一方面，下丘脑和皮层在发育过程中呈逐渐上升趋势，峰值出现在产后第13天到82天之间。相比之下，胃和嗅球在发育早期SRIF mRNA水平较低，在发育后期（产后第13天到82天）上升。每个区域内SRIF mRNA的量也存在显著差异。这些数据表明，在发育过程中，SRIF基因在脑的不同区域和胃中存在差异表达。对这一现象的进一步研究可能有助于深入了解SRIF基因表达的体内调控以及SRIF在发育中的大脑中的作用。
