Colorectal Neoplasia Decarboxylase Gene Sequences and Elevated Expression in Two Chromosomal Locations for Human Ornithine
نویسندگان
چکیده
The polyamines are known to be essential for cellular proliferation. Ornithine decarboxylase (OIK) is a rate-limiting enzyme in the synthesis of these amines, and activity is elevated in colorectal tumors and polyps. Two ODC genes (designated OIK I and ODC2) were localized by somatic cell hybridization and in situ techniques to 2p25 and 7q31-qter, respectively. Investigation of the expression of ODC in colorectal neo plasia reveals a consistent increase in niKNA expression compared with normal adjacent mucosa and control mucosa, ranging from 1.3to 12.2fold. No amplification of the loci was seen. Comparison of ODC mRNA expression with ODC activity from the same samples revealed no direct correlation, suggesting that regulation of ODC in this system occurs at the posttranscriptional level.
منابع مشابه
Two chromosomal locations for human ornithine decarboxylase gene sequences and elevated expression in colorectal neoplasia.
The polyamines are known to be essential for cellular proliferation. Ornithine decarboxylase (ODC) is a rate-limiting enzyme in the synthesis of these amines, and activity is elevated in colorectal tumors and polyps. Two ODC genes (designated ODC1 and ODC2) were localized by somatic cell hybridization and in situ techniques to 2p25 and 7q31-qter, respectively. Investigation of the expression of...
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