A small regulatory element from chromosome 19 enhances liver-specific gene expression.

Published

Journal Article

Tissue-specific promoters for gene therapy are typically too big for adeno-associated virus (AAV) vectors; thus, the exploration of small effective non-viral regulatory elements is of particular interest. Wild-type AAV can specifically integrate into a region on human chromosome 19 termed AAVS1. Earlier work has determined that a 347 bp fragment (Chr19) of AAVS1 has promoter and transcriptional enhancer activities. In this study, we further characterized this genetic regulation and investigated its application to AAV gene therapy in vitro and in vivo. The Chr19 347 bp fragment was dissected into three regulatory elements in human embryonic kidney cells: (i) TATA-independent promoter activity distributed throughout the fragment regardless of orientation, (ii) an orientation-dependent insulator function near the 5' end and (iii) a 107 bp enhancer region near the 3' end. The small enhancer region, coupled to the mini-CMV promoter, was used to drive the expression of several reporters following transduction by AAV2. In vivo data demonstrated enhanced transgene expression from the Chr19-mini-CMV promoter cassette after tail vein injection primarily in the liver at levels comparable to the chicken beta-actin promoter and higher than the liver-specific TTR promoter (>2-fold). However, we did not observe this increase after muscle injection, suggesting tissue-specific enhancement. All of the results support identification of a small DNA fragment (347 bp) from AAV Chr19 integration site capable of providing efficient and enhanced liver-specific transcription when used in recombinant AAV vectors.

Full Text

Duke Authors

Cited Authors

  • Li, C; Hirsch, M; Carter, P; Asokan, A; Zhou, X; Wu, Z; Samulski, RJ

Published Date

  • January 2009

Published In

Volume / Issue

  • 16 / 1

Start / End Page

  • 43 - 51

PubMed ID

  • 18701910

Pubmed Central ID

  • 18701910

Electronic International Standard Serial Number (EISSN)

  • 1476-5462

International Standard Serial Number (ISSN)

  • 0969-7128

Digital Object Identifier (DOI)

  • 10.1038/gt.2008.134

Language

  • eng