Intron 抑制斑馬魚 myf-5 基因表現的關鍵序列
Date Issued
2004-07-31
Date
2004-07-31
Author(s)
蔡懷楨
DOI
922313B002078
Abstract
Myf-5 is the one of the muscle regulatory factors involved in the proliferation
of myoblasts and differentiation of myogenic cells. Yet, the cis-regulatory elements
of myf-5 gene are not clearly defined. Due to no particularly suitable cell-lines
available for analyzing the gene regulation of zebrafish myf-5, in vivo transgenic
assay was employed. A plasmid which contained zebrafish myf-5 gene upstream
regulatory sequence from –9977 to –1 (-9977/-1), exon 1 (E1), intron 1 (I1), exon 2
(E2) and in frame fused with GFP [(-9977/-1)/E1/I1/E2/GFP], was constructed and
microinjected into one-cell embryos. Surprisingly, the somite-specific expression
rate was extremely low (2 %, n=392), compared to that (94 %) of embryos injected
with (–9977/–1)/GFP. Similar results were also obtained by injecting the constructs
of E1/I1/E2/GFP but fused with –7710/-1, -2937/-1 and –290/-1. To further study
the regulatory elements within the intron, various deletion fragments of intron 1
were finely dissected and fused with upstream -2937/-1 and GFP [(-2937/-1)/GFP].
The somite-specific expression rates were 2, 90, 88, 87, 83, 12, 10, 8 and 83 % for
embryos injected with (-2937/-1)/GFP fused with intron 1 +502/+2503,+1174/+2503, +1768/+2503, +790/+1489, +1467/+2152, +502/+1787, +502/+1199,
+502/+835 and +502/+659, respectively. Whereas, the somite-specific expression
rate of embryos injected with (-2937/-1)/GFP was 84 %, which was quite close (91
%) to that of embryos injected with fragment (-2937/-1)/GFP/(+502/+1199) but
absence of +660/+816 segment. These evidences strongly suggest that downstream
sequence of +660/+816 motif represses the expression of zebrafish myf-5 gene. This
is the first report to propose that an intron segment may be involved in delicately
controlling the somite-specific and stage-dependent expression of myf-5.
Subjects
intron
myf-5
regulatory cis-elements
repression
somite
Publisher
臺北市：國立臺灣大學漁業科學研究所
Type
journal article
File(s)![Thumbnail Image]()
Loading...
Name
922313B002078.pdf
Size
365.45 KB
Format
Adobe PDF
Checksum
(MD5):89d3abac510e0b5f6d04da6f4ae44765