Limits...
Annotated ESTs from various tissues of the brown planthopper Nilaparvata lugens: a genomic resource for studying agricultural pests.

Noda H, Kawai S, Koizumi Y, Matsui K, Zhang Q, Furukawa S, Shimomura M, Mita K - BMC Genomics (2008)

Bottom Line: An EST database is available at our web site.The EST library will provide useful information for transcriptional analyses, proteomic analyses, and gene functional analyses of BPH.Moreover, specific genes for hemimetabolous insects will be identified.

View Article: PubMed Central - HTML - PubMed

Affiliation: National Institute of Agrobiological Sciences, Owashi, Tsukuba, Ibaraki 305-8634, Japan. hnada@affrc.go.jp

ABSTRACT

Background: The brown planthopper (BPH), Nilaparvata lugens (Hemiptera, Delphacidae), is a serious insect pests of rice plants. Major means of BPH control are application of agricultural chemicals and cultivation of BPH resistant rice varieties. Nevertheless, BPH strains that are resistant to agricultural chemicals have developed, and BPH strains have appeared that are virulent against the resistant rice varieties. Expressed sequence tag (EST) analysis and related applications are useful to elucidate the mechanisms of resistance and virulence and to reveal physiological aspects of this non-model insect, with its poorly understood genetic background.

Results: More than 37,000 high-quality ESTs, excluding sequences of mitochondrial genome, microbial genomes, and rDNA, have been produced from 18 libraries of various BPH tissues and stages. About 10,200 clusters have been made from whole EST sequences, with average EST size of 627 bp. Among the top ten most abundantly expressed genes, three are unique and show no homology in BLAST searches. The actin gene was highly expressed in BPH, especially in the thorax. Tissue-specifically expressed genes were extracted based on the expression frequency among the libraries. An EST database is available at our web site.

Conclusion: The EST library will provide useful information for transcriptional analyses, proteomic analyses, and gene functional analyses of BPH. Moreover, specific genes for hemimetabolous insects will be identified. The microarray fabricated based on the EST information will be useful for finding genes related to agricultural and biological problems related to this pest.

Show MeSH

Related in: MedlinePlus

In situ hybridization of EST clone OC2756 (AA0383) in adult female and TA0721 in adult male. Left, anti-sense probe; right, sense probe. Signals were observed in a part of the lateral oviduct (OC2756) and in an accessory gland of the testis (TA0721).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC2311293&req=5

Figure 8: In situ hybridization of EST clone OC2756 (AA0383) in adult female and TA0721 in adult male. Left, anti-sense probe; right, sense probe. Signals were observed in a part of the lateral oviduct (OC2756) and in an accessory gland of the testis (TA0721).

Mentions: In this species, the ovary starts to mature one or two days after adult emergence. Library OA is made from the immature ovary and its accessory glands of 0–1 day old adults; OB and OC were made from mature ones of 4–5 days old. Libraries AA and AB were made from the female abdomen, which includes the female gonad. Therefore, the ESTs found only in the libraries OA, OB, OC, AA, and AB are candidate genes for female-gonad-specific expression. Table 4 shows the example of candidate ESTs of female-gonad-specifically expressed genes. These genes were selected by high-frequency expression in these five libraries and no expression in the other libraries. The ESTs that show expression in the libraries OB and OC and no expression in the library OA (e.g. EST clones AB0551, OB0998, OB1061, OC0638, OC0681) were probably expressed in the mature ovary and accessory glands. The restricted expression of these genes in the female gonad was confirmed by RT-PCR. Figure 7 shows the restricted gene expression of EST clone OC2756 in the female gonad and abdomen. In situ hybridization showed expression of this gene in the lateral oviduct (Fig. 8) as described previously. Further examination is necessary for characterizing these genes in ovarian development of BPH.


Annotated ESTs from various tissues of the brown planthopper Nilaparvata lugens: a genomic resource for studying agricultural pests.

Noda H, Kawai S, Koizumi Y, Matsui K, Zhang Q, Furukawa S, Shimomura M, Mita K - BMC Genomics (2008)

In situ hybridization of EST clone OC2756 (AA0383) in adult female and TA0721 in adult male. Left, anti-sense probe; right, sense probe. Signals were observed in a part of the lateral oviduct (OC2756) and in an accessory gland of the testis (TA0721).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2311293&req=5

Figure 8: In situ hybridization of EST clone OC2756 (AA0383) in adult female and TA0721 in adult male. Left, anti-sense probe; right, sense probe. Signals were observed in a part of the lateral oviduct (OC2756) and in an accessory gland of the testis (TA0721).
Mentions: In this species, the ovary starts to mature one or two days after adult emergence. Library OA is made from the immature ovary and its accessory glands of 0–1 day old adults; OB and OC were made from mature ones of 4–5 days old. Libraries AA and AB were made from the female abdomen, which includes the female gonad. Therefore, the ESTs found only in the libraries OA, OB, OC, AA, and AB are candidate genes for female-gonad-specific expression. Table 4 shows the example of candidate ESTs of female-gonad-specifically expressed genes. These genes were selected by high-frequency expression in these five libraries and no expression in the other libraries. The ESTs that show expression in the libraries OB and OC and no expression in the library OA (e.g. EST clones AB0551, OB0998, OB1061, OC0638, OC0681) were probably expressed in the mature ovary and accessory glands. The restricted expression of these genes in the female gonad was confirmed by RT-PCR. Figure 7 shows the restricted gene expression of EST clone OC2756 in the female gonad and abdomen. In situ hybridization showed expression of this gene in the lateral oviduct (Fig. 8) as described previously. Further examination is necessary for characterizing these genes in ovarian development of BPH.

Bottom Line: An EST database is available at our web site.The EST library will provide useful information for transcriptional analyses, proteomic analyses, and gene functional analyses of BPH.Moreover, specific genes for hemimetabolous insects will be identified.

View Article: PubMed Central - HTML - PubMed

Affiliation: National Institute of Agrobiological Sciences, Owashi, Tsukuba, Ibaraki 305-8634, Japan. hnada@affrc.go.jp

ABSTRACT

Background: The brown planthopper (BPH), Nilaparvata lugens (Hemiptera, Delphacidae), is a serious insect pests of rice plants. Major means of BPH control are application of agricultural chemicals and cultivation of BPH resistant rice varieties. Nevertheless, BPH strains that are resistant to agricultural chemicals have developed, and BPH strains have appeared that are virulent against the resistant rice varieties. Expressed sequence tag (EST) analysis and related applications are useful to elucidate the mechanisms of resistance and virulence and to reveal physiological aspects of this non-model insect, with its poorly understood genetic background.

Results: More than 37,000 high-quality ESTs, excluding sequences of mitochondrial genome, microbial genomes, and rDNA, have been produced from 18 libraries of various BPH tissues and stages. About 10,200 clusters have been made from whole EST sequences, with average EST size of 627 bp. Among the top ten most abundantly expressed genes, three are unique and show no homology in BLAST searches. The actin gene was highly expressed in BPH, especially in the thorax. Tissue-specifically expressed genes were extracted based on the expression frequency among the libraries. An EST database is available at our web site.

Conclusion: The EST library will provide useful information for transcriptional analyses, proteomic analyses, and gene functional analyses of BPH. Moreover, specific genes for hemimetabolous insects will be identified. The microarray fabricated based on the EST information will be useful for finding genes related to agricultural and biological problems related to this pest.

Show MeSH
Related in: MedlinePlus