Systematic cloning and analysis of autophagy-related genes from the silkworm Bombyx mori.
BACKGROUND
Through the whole life of eukaryotes, autophagy plays an important role in various biological events including development, differentiation and determination of lifespan. A full set of genes and their encoded proteins of this evolutionarily conserved pathway have been identified in many eukaryotic organisms from yeast to mammals. However, this pathway in the insect model organism, the silkworm Bombyx mori, remains poorly investigated.


RESULTS
Based on the autophagy pathway in several model organisms and a series of bioinformatic analyses, we have found more than 20 autophagy-related genes from the current database of the silkworm Bombyx mori. These genes could be further classified into the signal transduction pathway and two ubiquitin-like pathways. Using the mRNA extracted from the silkgland, we cloned the full length cDNA fragments of some key genes via reverse transcription PCR and 3' rapid amplification of cDNA ends (RACE). In addition, we found that the transcription levels of two indicator genes BmATG8 and BmATG12 in the silkgland tend to be increased from 1st to 8th day of the fifth instar larvae.


CONCLUSIONS
Bioinformatics in combination with RT-PCR enable us to remodel a preliminary pathway of autophagy in the silkworm. Amplification and cloning of most autophagy-related genes from the silkgland indicated autophagy is indeed an activated process. Furthermore, the time-course transcriptional profiles of BmATG8 and BmATG12 revealed that both genes are up-regulated along the maturation of the silkgland during the fifth instar. These findings suggest that the autophagy should play an important role in Bombyx mori silkgland.
Zhang
Xuan
X
Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei Anhui 230027, PR China. xuanz@mail.ustc.edu.cn
Hu
Zhan-Ying
ZY
Li
Wei-Fang
WF
Li
Qing-Rong
QR
Deng
Xiao-Juan
XJ
Yang
Wan-Ying
WY
Cao
Yang
Y
Zhou
Cong-Zhao
CZ
D000595:Amino Acid Sequence; D000818:Animals; D001343:Autophagy; D012831:Bombyx / Q000737:chemistry / Q000166:cytology* / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D005786:Gene Expression Regulation; D019476:Insect Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D015398:Signal Transduction
D019476:Insect Proteins