TY - JOUR
T1 - Characterization of the kynurenine 3-monooxygenase gene corresponding to the white egg 1 mutant in the silkworm Bombyx mori
AU - Quan, G. X.
AU - Kim, I.
AU - Kômoto, N.
AU - Sezutsu, H.
AU - Ote, M.
AU - Shimada, T.
AU - Kanda, T.
AU - Mita, K.
AU - Kobayashi, M.
AU - Tamura, T.
N1 - Funding Information:
Acknowledgements We thank Dr. K. Yukuhiro for useful discussions and Dr. M. Goldsmith for critical reading of th e manuscript. G. X. Quan is grateful to the Science and Technology Agency of Japan for financial support. This work was supported by MAFF and the Program for the Promotion of Basic Research Activities for Innovative Bioscience, Japan.
PY - 2002
Y1 - 2002
N2 - Kynurenine 3-monooxygenase (KMO, EC 1.14.13.9), which catalyzes the oxidation of kynurenine to 3-hydroxykynurenine, is involved in the synthesis of ommochrome pigments in insects. A silkworm mutant, white egg 1 (w-1), has been shown to be deficient in this enzyme activity. The mutant is characterized morphologically by its white eyes and the fact that the females lay white eggs. To analyze the relationship between the KMO gene and the mutation, we first determined the entire sequence of a full-length 2.0-kb cDNA and examined its expression pattern in the wild type. The cDNA sequence contains one ORF encoding a polypeptide of 456 amino acids, and transcripts were detected in the larval Malpighian tubules and the pupal ovaries, but not in other tissues. Southern analysis and nucleotide sequencing showed that the KMO gene is present in a single copy and consists of ten exons distributed over a 16-kb region. Comparison of the transcripts between the wild type and mutant silkworms showed that the wild type expressed a single transcript, whereas the mutant exhibited markedly reduced amounts of two transcripts with sizes of 2.0 kb and 1.8 kb. Nucleotide sequence analysis of these mutant transcripts indicated that sequences corresponding to the ninth and tenth exons were missing. Inverse PCR and Southern analysis of the mutant gene demonstrated that the corresponding genomic region was deleted in the w-1 mutant.
AB - Kynurenine 3-monooxygenase (KMO, EC 1.14.13.9), which catalyzes the oxidation of kynurenine to 3-hydroxykynurenine, is involved in the synthesis of ommochrome pigments in insects. A silkworm mutant, white egg 1 (w-1), has been shown to be deficient in this enzyme activity. The mutant is characterized morphologically by its white eyes and the fact that the females lay white eggs. To analyze the relationship between the KMO gene and the mutation, we first determined the entire sequence of a full-length 2.0-kb cDNA and examined its expression pattern in the wild type. The cDNA sequence contains one ORF encoding a polypeptide of 456 amino acids, and transcripts were detected in the larval Malpighian tubules and the pupal ovaries, but not in other tissues. Southern analysis and nucleotide sequencing showed that the KMO gene is present in a single copy and consists of ten exons distributed over a 16-kb region. Comparison of the transcripts between the wild type and mutant silkworms showed that the wild type expressed a single transcript, whereas the mutant exhibited markedly reduced amounts of two transcripts with sizes of 2.0 kb and 1.8 kb. Nucleotide sequence analysis of these mutant transcripts indicated that sequences corresponding to the ninth and tenth exons were missing. Inverse PCR and Southern analysis of the mutant gene demonstrated that the corresponding genomic region was deleted in the w-1 mutant.
KW - Bombyx mori
KW - Kynurenine 3-monooxygenase
KW - Silkworm
KW - Transgenic animal
KW - White egg 1
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U2 - 10.1007/s00438-001-0629-2
DO - 10.1007/s00438-001-0629-2
M3 - Article
C2 - 11919709
AN - SCOPUS:18344388797
VL - 267
SP - 1
EP - 9
JO - Zeitschrift für Induktive Abstammungs- und Vererbungslehre
JF - Zeitschrift für Induktive Abstammungs- und Vererbungslehre
SN - 1617-4615
IS - 1
ER -