Limits...
Analysis of four achaete-scute homologs in Bombyx mori reveals new viewpoints of the evolution and functions of this gene family.

Zhou Q, Zhang T, Xu W, Yu L, Yi Y, Zhang Z - BMC Genet. (2008)

Bottom Line: Functions besides neural development controlling have also been found in Drosophila AS-C genes.Proteins encoded by them contained the characteristic bHLH domain and the three proneural ones were also found to have the C-terminal conserved motif.AS-C gene duplication in insects occurs after or parallel to, but not before the taxonomic order formation during evolution.

View Article: PubMed Central - HTML - PubMed

Affiliation: The Biotechnology Research Institute, National Engineering of crop germplasm and genetic improvement, Chinese Academy of Agricultural Sciences, Beijing, 100081, China. Qingxiang_Zhou@meei.harvard.edu

ABSTRACT

Background: achaete-scute complexe (AS-C) has been widely studied at genetic, developmental and evolutional levels. Genes of this family encode proteins containing a highly conserved bHLH domain, which take part in the regulation of the development of central nervous system and peripheral nervous system. Many AS-C homologs have been isolated from various vertebrates and invertebrates. Also, AS-C genes are duplicated during the evolution of Diptera. Functions besides neural development controlling have also been found in Drosophila AS-C genes.

Results: We cloned four achaete-scute homologs (ASH) from the lepidopteran model organism Bombyx mori, including three proneural genes and one neural precursor gene. Proteins encoded by them contained the characteristic bHLH domain and the three proneural ones were also found to have the C-terminal conserved motif. These genes regulated promoter activity through the Class A E-boxes in vitro. Though both Bm-ASH and Drosophila AS-C have four members, they are not in one by one corresponding relationships. Results of RT-PCR and real-time PCR showed that Bm-ASH genes were expressed in different larval tissues, and had well-regulated expressional profiles during the development of embryo and wing/wing disc.

Conclusion: There are four achaete-scute homologs in Bombyx mori, the second insect having four AS-C genes so far, and these genes have multiple functions in silkworm life cycle. AS-C gene duplication in insects occurs after or parallel to, but not before the taxonomic order formation during evolution.

Show MeSH
The data curves (upper) and melting curves (lower) of Quantitative real-time PCR for Bm-actin A3 and Bm-ASH genes. These are the curves of amplifications for standard curve making. The plots show that the repeatability and specification of the Q-PCR are good.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC2315653&req=5

Figure 9: The data curves (upper) and melting curves (lower) of Quantitative real-time PCR for Bm-actin A3 and Bm-ASH genes. These are the curves of amplifications for standard curve making. The plots show that the repeatability and specification of the Q-PCR are good.

Mentions: Standard curves were constructed using serial dilutions of the ORF segments of the genes recombined into pMD18-T vectors (Takara, Japan). The log ranges of the standard curves were from 106 to 102 copies. The data curve and the melting curve showed the reliability and specificity of the PCR product (Fig. 9). Threshold cycles of each standard dilution point were used to generate a reliable standard curve for each gene (Fig. 10). Linear equations corresponding to each standard curve were made, and R2 for each standard curve was more than 0.99. This showed that the linearity of the standard curves was good.


Analysis of four achaete-scute homologs in Bombyx mori reveals new viewpoints of the evolution and functions of this gene family.

Zhou Q, Zhang T, Xu W, Yu L, Yi Y, Zhang Z - BMC Genet. (2008)

The data curves (upper) and melting curves (lower) of Quantitative real-time PCR for Bm-actin A3 and Bm-ASH genes. These are the curves of amplifications for standard curve making. The plots show that the repeatability and specification of the Q-PCR are good.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2315653&req=5

Figure 9: The data curves (upper) and melting curves (lower) of Quantitative real-time PCR for Bm-actin A3 and Bm-ASH genes. These are the curves of amplifications for standard curve making. The plots show that the repeatability and specification of the Q-PCR are good.
Mentions: Standard curves were constructed using serial dilutions of the ORF segments of the genes recombined into pMD18-T vectors (Takara, Japan). The log ranges of the standard curves were from 106 to 102 copies. The data curve and the melting curve showed the reliability and specificity of the PCR product (Fig. 9). Threshold cycles of each standard dilution point were used to generate a reliable standard curve for each gene (Fig. 10). Linear equations corresponding to each standard curve were made, and R2 for each standard curve was more than 0.99. This showed that the linearity of the standard curves was good.

Bottom Line: Functions besides neural development controlling have also been found in Drosophila AS-C genes.Proteins encoded by them contained the characteristic bHLH domain and the three proneural ones were also found to have the C-terminal conserved motif.AS-C gene duplication in insects occurs after or parallel to, but not before the taxonomic order formation during evolution.

View Article: PubMed Central - HTML - PubMed

Affiliation: The Biotechnology Research Institute, National Engineering of crop germplasm and genetic improvement, Chinese Academy of Agricultural Sciences, Beijing, 100081, China. Qingxiang_Zhou@meei.harvard.edu

ABSTRACT

Background: achaete-scute complexe (AS-C) has been widely studied at genetic, developmental and evolutional levels. Genes of this family encode proteins containing a highly conserved bHLH domain, which take part in the regulation of the development of central nervous system and peripheral nervous system. Many AS-C homologs have been isolated from various vertebrates and invertebrates. Also, AS-C genes are duplicated during the evolution of Diptera. Functions besides neural development controlling have also been found in Drosophila AS-C genes.

Results: We cloned four achaete-scute homologs (ASH) from the lepidopteran model organism Bombyx mori, including three proneural genes and one neural precursor gene. Proteins encoded by them contained the characteristic bHLH domain and the three proneural ones were also found to have the C-terminal conserved motif. These genes regulated promoter activity through the Class A E-boxes in vitro. Though both Bm-ASH and Drosophila AS-C have four members, they are not in one by one corresponding relationships. Results of RT-PCR and real-time PCR showed that Bm-ASH genes were expressed in different larval tissues, and had well-regulated expressional profiles during the development of embryo and wing/wing disc.

Conclusion: There are four achaete-scute homologs in Bombyx mori, the second insect having four AS-C genes so far, and these genes have multiple functions in silkworm life cycle. AS-C gene duplication in insects occurs after or parallel to, but not before the taxonomic order formation during evolution.

Show MeSH