摘要
A β-actin gene, Libβ-actinl, from the psocid, Liposcelis bostrychophila, was isolated, sequenced, and expressed in Escherichia coll. The cDNA sequence was 1 281 bp in length and contained an open reading frame of 1 131 bp encoding 376 amino acids with a predicted molecular weight of 41.82 kDa. According to a B lastN search, the coding region shared the highest identity （97%） with Pediculus hurnanus actin 5C, while the deduced amino acid sequence was completely identical to a mutant of Drosophila melanogaster actin 5C. Comparison of the nucleotide and deduced amino acid sequences confirmed the high similarity between Libβ-actinl and homologs in other insect species. The 3＇ untranslated region （3＇ UTR） of the Libβ-actinl mRNA had a high A＋U content （approximately 75%） and contained three repeats of the AUUUUUA and AUUUA motifs, which may play a role in regulating mRNA decay. The expression of Libβ-actinl was further analyzed in insecticide induced and control psocids. The results indicated that there was no significant difference in expression of Libβ-actinl between the induced and control groups, suggesting that Libβ-actinl may be an appropriate internal control for the gene expression profiling in this insect. Furthermore, Libβ-actinl was also heterologously expressed in Escherichia coli, which provided a basis to investigate the physiological functions of actin genes in the psocid.
A β-actin gene, Libβ-actinl, from the psocid, Liposcelis bostrychophila, was isolated, sequenced, and expressed in Escherichia coll. The cDNA sequence was 1 281 bp in length and contained an open reading frame of 1 131 bp encoding 376 amino acids with a predicted molecular weight of 41.82 kDa. According to a B lastN search, the coding region shared the highest identity （97%） with Pediculus hurnanus actin 5C, while the deduced amino acid sequence was completely identical to a mutant of Drosophila melanogaster actin 5C. Comparison of the nucleotide and deduced amino acid sequences confirmed the high similarity between Libβ-actinl and homologs in other insect species. The 3＇ untranslated region （3＇ UTR） of the Libβ-actinl mRNA had a high A＋U content （approximately 75%） and contained three repeats of the AUUUUUA and AUUUA motifs, which may play a role in regulating mRNA decay. The expression of Libβ-actinl was further analyzed in insecticide induced and control psocids. The results indicated that there was no significant difference in expression of Libβ-actinl between the induced and control groups, suggesting that Libβ-actinl may be an appropriate internal control for the gene expression profiling in this insect. Furthermore, Libβ-actinl was also heterologously expressed in Escherichia coli, which provided a basis to investigate the physiological functions of actin genes in the psocid.
基金
funded in part by the National Natural Sciences Foundation of China (30871631,31000860)
the Specialized Research Fund for the Doctoral Program of Higher Education, China(200806350009)
the Science and Technology Innovation Foundation for Graduate Students (kb2008001) of Southwest University, China
