Inhibition of type I procollagen production by tRNAVal CTE-HSP47 ribozyme.
BACKGROUND
Fibrosis characteristically occurs in the advanced stages of chronic inflammatory diseases, occasionally as the primary lesion, and frequently determines the disease prognosis. Fibrotic lesions consist mostly of collagen, and therefore it may be possible to prevent or treat fibrosis by inhibiting collagen production. Of the currently available therapeutic approaches, however, none is sufficiently effective and specific for inhibition of collagen. Heat shock protein 47 (HSP47) is a collagen-specific molecular chaperone that has been reported to play a pivotal role in secretion of procollagen molecules. Therefore, we have tried to suppress its function to inhibit these various types of collagen.


METHODS
We have developed a novel type of ribozyme by ligating a hammerhead sequence to a tRNA(Val) promoter to facilitate displacing the ribozyme from nucleus to cytoplasm and to constitutive transport element, a binding motif of helicase which unwinds mRNA to render the target sequence on the mRNA accessible to the ribozyme.


RESULTS
The ribozyme thus constructed showed strong activity to cleave HSP47 mRNA and suppress the secretion of type I procollagen in the human primary fibroblast.


CONCLUSIONS
We suggest applicability of this ribozyme as a new modality for antifibrosis therapy.
Hagiwara
Seiya
S
The 4th Department of Internal Medicine, Sapporo Medical University School of Medicine, Sapporo, Japan.
Nakamura
Kiminori
K
Hamada
Hirofumi
H
Sasaki
Katsunori
K
Ito
Yoshinori
Y
Kuribayashi
Kageaki
K
Sato
Tsutomu
T
Sato
Yasushi
Y
Takahashi
Minoru
M
Kogawa
Katsuhisa
K
Kato
Junji
J
Terui
Takeshi
T
Takayama
Tetsuji
T
Matsunaga
Takuya
T
Taira
Kazunari
K
Niitsu
Yoshiro
Y
D016375:Antisense Elements (Genetics) / Q000235:genetics; D001483:Base Sequence; D024042:Collagen Type I / Q000096:biosynthesis* / Q000378:metabolism; D005786:Gene Expression Regulation; D050958:HSP47 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D010957:Plasmids / Q000235:genetics; D012313:RNA / Q000235:genetics / Q000378:metabolism; D016337:RNA, Catalytic / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D012366:RNA, Transfer, Val / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012045:Regulatory Sequences, Nucleic Acid; D020218:Response Elements
D016375:Antisense Elements (Genetics); D024042:Collagen Type I; D050958:HSP47 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D016337:RNA, Catalytic; D012366:RNA, Transfer, Val; D011993:Recombinant Fusion Proteins; C494660:SERPINH1 protein, human; C427204:hammerhead ribozyme; D012313:RNA; D008156:Luciferases