TY - JOUR
T1 - Study of the aminopeptidase N gene family in the lepidopterans Ostrinia nubilalis (Hübner) and Bombyx mori (L.)
T2 - Sequences, mapping and expression
AU - Crava, Cristina M.
AU - Bel, Yolanda
AU - Lee, Siu Fai
AU - Manachini, Barbara
AU - Heckel, David G.
AU - Escriche, Baltasar
PY - 2010/7
Y1 - 2010/7
N2 - Aminopeptidases N (APNs) are a class of ectoenzymes present in lepidopteran larvae midguts, involved in the Bacillus thuringiensis (Bt) toxins mode of action. In the present work, seven aminopeptidases have been cloned from the midgut of Ostrinia nubilalis, the major Lepidopteran corn pest in the temperate climates. Six sequences were identified as APNs because of the presence of the HEXXH(X)18E and GAMEN motifs, as well as the signal peptide and the GPI-anchor sequences. The remaining sequence did not contain the two cellular targeting signals, indicating it belonged to the puromycin-sensitive aminopeptidase (PSA) family. An in silico analysis allowed us to find orthologous sequences in Bombyx mori. A phylogenetic study of lepidopteran aminopeptidase sequences resulted in their clustering into nine classes. Linkage analysis revealed that the onapn genes as well as all bmapn genes clustered in a single linkage group. O. nubilalis aminopeptidases were expressed in all larval instars. In 5th instar larvae tissues, apns transcripts were found mainly in midguts while apn8 was also highly expressed in Malpighian tubules, and psa showed an ubiquitous expression pattern in O. nubilalis and B. mori. The sequence homology and gene organization of apns suggest a single origin from an ancestral lepidopteran apn gene.
AB - Aminopeptidases N (APNs) are a class of ectoenzymes present in lepidopteran larvae midguts, involved in the Bacillus thuringiensis (Bt) toxins mode of action. In the present work, seven aminopeptidases have been cloned from the midgut of Ostrinia nubilalis, the major Lepidopteran corn pest in the temperate climates. Six sequences were identified as APNs because of the presence of the HEXXH(X)18E and GAMEN motifs, as well as the signal peptide and the GPI-anchor sequences. The remaining sequence did not contain the two cellular targeting signals, indicating it belonged to the puromycin-sensitive aminopeptidase (PSA) family. An in silico analysis allowed us to find orthologous sequences in Bombyx mori. A phylogenetic study of lepidopteran aminopeptidase sequences resulted in their clustering into nine classes. Linkage analysis revealed that the onapn genes as well as all bmapn genes clustered in a single linkage group. O. nubilalis aminopeptidases were expressed in all larval instars. In 5th instar larvae tissues, apns transcripts were found mainly in midguts while apn8 was also highly expressed in Malpighian tubules, and psa showed an ubiquitous expression pattern in O. nubilalis and B. mori. The sequence homology and gene organization of apns suggest a single origin from an ancestral lepidopteran apn gene.
KW - Bt toxin-binding proteins
KW - Larval development expression
KW - Midgut APN
KW - Puromycin-sensitive aminopeptidase
KW - Quantitative PCR
UR - http://www.scopus.com/inward/record.url?scp=77953911945&partnerID=8YFLogxK
U2 - 10.1016/j.ibmb.2010.04.010
DO - 10.1016/j.ibmb.2010.04.010
M3 - Article
C2 - 20420910
AN - SCOPUS:77953911945
VL - 40
SP - 506
EP - 515
JO - Insect Biochemistry and Molecular Biology
JF - Insect Biochemistry and Molecular Biology
SN - 0965-1748
IS - 7
ER -