抄録
Albino (al) is a lethal mutant of Bombyx mori that exhibits a colourless cuticle after the first ecdysis and dies without feeding on mulberry. Previous studies have indicated that sclerotisation was insufficient because of defective phenylalanine and tyrosine metabolism in albino larvae. However, the genetic mechanism underlying the albino phenotype has not been determined. Dopamine plays a central role in insect cuticle colouration and sclerotisation. The pathway for dopamine biosynthesis from phenylalanine involves phenylalanine hydroxylase (PAH; EC 1.14.16.1) and tyrosine hydroxylase (TH; EC 1.14.16.2). Tetrahydrobiopterin (BH4) is an essential cofactor of aromatic amino acid hydroxylases, including PAH and TH. Thus, BH4 is indispensable for cuticle colouration and sclerotisation. Here we report on identifying mutations in the gene that encodes for the Bombyx homolog of 6-pyruvoyl-tetrahydropterin synthase (PTS) which is involved in the biosynthesis of BH4, in 2 strains with different al alleles. In strain a60 (al), a transposable element was inserted in exon 2 of BmPTS. In strain a61 (al2), an 11-bp deletion was identified in the exon 2 region of BmPTS. After oral administration of BH4 to the al2 larvae, the survival rate was effectively increased and the larval integument was pigmented. These results indicated that BmPTS was responsible for the albino mutants of B.mori. We conclude that (i) a mutation in BmPTS leads to an insufficient supply of BH4 and results in defective dopamine biosynthesis and (ii) lack of dopamine results in cuticle colouration and sclerotisation failure. Lemon (lem) is a BH4-deficient mutant. It has been reported that de novo synthesis of zygotic BH4 was indispensable for viability of the embryo in eggs laid by lem (lem/leml) females. We found that lem/lem, al2/al2 larvae produced by lem (lem/lem) females were viable during the first instar stage, suggesting that al2/al2 embryo could synthesis BH4 by using maternally transmitted BmPTS.
| 元の言語 | 英語 |
|---|---|
| ページ（範囲） | 594-600 |
| ページ数 | 7 |
| ジャーナル | Insect Biochemistry and Molecular Biology |
| 巻 | 43 |
| 発行部数 | 7 |
| DOI | |
| 出版物ステータス | 出版済み - 7 1 2013 |
Fingerprint
All Science Journal Classification (ASJC) codes
- Biochemistry
- Molecular Biology
- Insect Science
これを引用
Albino (al) is a tetrahydrobiopterin (BH4)-deficient mutant of the silkworm Bombyx mori. / Fujii, Tsuguru; Abe, Hiroaki; Kawamoto, Munetaka; Katsuma, Susumu; Banno, Yutaka; Shimada, Toru.
：: Insect Biochemistry and Molecular Biology, 巻 43, 番号 7, 01.07.2013, p. 594-600.研究成果: ジャーナルへの寄稿 › 記事
}
TY - JOUR
T1 - Albino (al) is a tetrahydrobiopterin (BH4)-deficient mutant of the silkworm Bombyx mori
AU - Fujii, Tsuguru
AU - Abe, Hiroaki
AU - Kawamoto, Munetaka
AU - Katsuma, Susumu
AU - Banno, Yutaka
AU - Shimada, Toru
PY - 2013/7/1
Y1 - 2013/7/1
N2 - Albino (al) is a lethal mutant of Bombyx mori that exhibits a colourless cuticle after the first ecdysis and dies without feeding on mulberry. Previous studies have indicated that sclerotisation was insufficient because of defective phenylalanine and tyrosine metabolism in albino larvae. However, the genetic mechanism underlying the albino phenotype has not been determined. Dopamine plays a central role in insect cuticle colouration and sclerotisation. The pathway for dopamine biosynthesis from phenylalanine involves phenylalanine hydroxylase (PAH; EC 1.14.16.1) and tyrosine hydroxylase (TH; EC 1.14.16.2). Tetrahydrobiopterin (BH4) is an essential cofactor of aromatic amino acid hydroxylases, including PAH and TH. Thus, BH4 is indispensable for cuticle colouration and sclerotisation. Here we report on identifying mutations in the gene that encodes for the Bombyx homolog of 6-pyruvoyl-tetrahydropterin synthase (PTS) which is involved in the biosynthesis of BH4, in 2 strains with different al alleles. In strain a60 (al), a transposable element was inserted in exon 2 of BmPTS. In strain a61 (al2), an 11-bp deletion was identified in the exon 2 region of BmPTS. After oral administration of BH4 to the al2 larvae, the survival rate was effectively increased and the larval integument was pigmented. These results indicated that BmPTS was responsible for the albino mutants of B.mori. We conclude that (i) a mutation in BmPTS leads to an insufficient supply of BH4 and results in defective dopamine biosynthesis and (ii) lack of dopamine results in cuticle colouration and sclerotisation failure. Lemon (lem) is a BH4-deficient mutant. It has been reported that de novo synthesis of zygotic BH4 was indispensable for viability of the embryo in eggs laid by lem (lem/leml) females. We found that lem/lem, al2/al2 larvae produced by lem (lem/lem) females were viable during the first instar stage, suggesting that al2/al2 embryo could synthesis BH4 by using maternally transmitted BmPTS.
AB - Albino (al) is a lethal mutant of Bombyx mori that exhibits a colourless cuticle after the first ecdysis and dies without feeding on mulberry. Previous studies have indicated that sclerotisation was insufficient because of defective phenylalanine and tyrosine metabolism in albino larvae. However, the genetic mechanism underlying the albino phenotype has not been determined. Dopamine plays a central role in insect cuticle colouration and sclerotisation. The pathway for dopamine biosynthesis from phenylalanine involves phenylalanine hydroxylase (PAH; EC 1.14.16.1) and tyrosine hydroxylase (TH; EC 1.14.16.2). Tetrahydrobiopterin (BH4) is an essential cofactor of aromatic amino acid hydroxylases, including PAH and TH. Thus, BH4 is indispensable for cuticle colouration and sclerotisation. Here we report on identifying mutations in the gene that encodes for the Bombyx homolog of 6-pyruvoyl-tetrahydropterin synthase (PTS) which is involved in the biosynthesis of BH4, in 2 strains with different al alleles. In strain a60 (al), a transposable element was inserted in exon 2 of BmPTS. In strain a61 (al2), an 11-bp deletion was identified in the exon 2 region of BmPTS. After oral administration of BH4 to the al2 larvae, the survival rate was effectively increased and the larval integument was pigmented. These results indicated that BmPTS was responsible for the albino mutants of B.mori. We conclude that (i) a mutation in BmPTS leads to an insufficient supply of BH4 and results in defective dopamine biosynthesis and (ii) lack of dopamine results in cuticle colouration and sclerotisation failure. Lemon (lem) is a BH4-deficient mutant. It has been reported that de novo synthesis of zygotic BH4 was indispensable for viability of the embryo in eggs laid by lem (lem/leml) females. We found that lem/lem, al2/al2 larvae produced by lem (lem/lem) females were viable during the first instar stage, suggesting that al2/al2 embryo could synthesis BH4 by using maternally transmitted BmPTS.
UR - http://www.scopus.com/inward/record.url?scp=84877884764&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84877884764&partnerID=8YFLogxK
U2 - 10.1016/j.ibmb.2013.03.009
DO - 10.1016/j.ibmb.2013.03.009
M3 - Article
VL - 43
SP - 594
EP - 600
JO - Insect Biochemistry and Molecular Biology
JF - Insect Biochemistry and Molecular Biology
SN - 0965-1748
IS - 7
ER -