[Sequencing of adenovirus type 7 vaccine strain fragment and characterization of the hexon encoding gene].
OBJECTIVE
To complete the full-length sequencing of the human adenovirus type 7 vaccine strain (Ad7v) for novel vector constructing.


METHODS
The Ad7v DNA was digested with SalI and the 17.5-68.0 map unit (mu) fragment was cloned and sequenced. The homology of encoding sequence of Ad7v hexon to those of group A,C,D,E,F and other numbers of group B was accomplished with the software CLUSTAL.V. The three-dimensional structure of the Ad7v hexon was predicted with the RasMo12.71.


RESULTS
The fragment contains 17,596 bp, part of E2 and late gene L1, L2 and L3 were encoded by this region. Polypeptide encoded by hexon gene lies in L3 region, which is composed of 934 amino acids. Multiple sequence alignment with the other nine known hexon protein sequences suggested that the variable sequences are mainly concentrated on seven regions, namely hypervariable regions (HVRs). The seven HVRs are related to type-specificity and group-specificity. The three-dimensional structure of the Ad7v hexon revealed that the variable regions are located in the I1 and I2 loops of the molecule mostly on the tower of the hexon.


CONCLUSIONS
The full-length genome sequencing of Ad7v was accomplished at last. Since the deduced amino acid sequence of Ad7v hexon was quite different from other adenoviral vectors such as Ad5 and Ad2, this virus can be potentially used for the construction of novel gene delivery vectors to counterpart the immunity to the vectors widely used at present.
Jiang
Xiu-li
XL
Department of Diarrhea Viruses Institute for Viral Disease Control and Prevention, Chinese Center For Disease Control and Prevention, Beijing 100052, China.
Wang
Jian-wei
JW
Wen
Le-ying
LY
Shi
Chang-xin
CX
Hong
Tao
T
D017503:Adenovirus E3 Proteins / Q000737:chemistry*; D000260:Adenoviruses, Human / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D036022:Capsid Proteins / Q000737:chemistry*; D005822:Genetic Vectors; D017386:Sequence Homology, Amino Acid; D014765:Viral Vaccines / Q000737:chemistry*
D017503:Adenovirus E3 Proteins; D036022:Capsid Proteins; D014765:Viral Vaccines; C018315:hexon capsid protein, Adenovirus