The Role of C-Terminus of Insulin B Chain
and the Amino Group of B29Lys Side Chain in the Growth Promoting Activities of
Insulin
MA Jian-Guo, LI Mo-Yi, ZHEN Ji-Min, CUI Da-Fu, FENG You-Min1
and JING Nai-He*
( Shanghai Institute of Biochemistry, Chinese Academy of Sciences, Shanghai
200031, China;
1 State key Laboratory of Molecular Biology, Shanghai Institute
of Biochemistry,
Chinese Academy of Sciences, Shanghai 200031, China )
Abstract By growing the mouse mammary
tumor-derived cell line GR2H6 in 96-well plates, we have developed an in
vitro bioassay for the growth promoting activities of insulin. This
bioassay system offers several advantages over currently used alternatives,
such as higher sensitivity, better reproducibility and the processing of many
samples simultaneously. Using this method, the mitogenic activities of insulin
and its analogues were studied. The analogue with elongated C-tenminus of
insulin B chain (［B31Lys］Ins-NH2) had a
higher mitogenic activity than insulin (130% of insulin). The mitogenic
activities of analogues with B29Lys amino group blocked was one third of those
with B29Lys amino group free, indicating that the C-terminal part of B chain
and the amino group of B29Lys were important for the growth promoting
activities of insulin.
Key Words Insulin; growth promoting
activities; bioassay; crystal violet
Corresponding author:
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