Project description:These two 3' Long SAGE libraries were constructed from stage 1-3 or stage 2-3 Bombyx egg chambers. Keywords: 3' Long SAGE libraries
Project description:To identify functions that distinguish the posterior and median cells producing fibroin and sericin in the silk gland of Bombyx mori, serial analysis of gene expression (SAGE) profiles from both silk gland regions were analyzed and compared. The construction of a B. mori reference tag collection extracted from a set of 38000 Bombyx EST sequenced from the 3’ side, helped annotating the SAGE libraries. Most of the tags appeared at similar relative concentration in the two libraries except for those corresponding to silk proteins that were found region-specific and highly abundant. Strikingly, besides tags from silk protein mRNAs, 19 tags were found in the class of high abundance in the median cell library, which were absent in the posterior cell tag collection. Except tags from SP1 mRNA, no PSG specific tags were found in the same class of abundance. The analysis of MSG-specific different transcripts led to suggest that middle silk gland cell realizes more diversified functions as those already known, of synthesis and secretion of the silk sericins.
Project description:These two 3' Long SAGE libraries were constructed from stage 1-3 or stage 2-3 Bombyx egg chambers. Keywords: 3' Long SAGE libraries These libraries were constructed as described in Saha et al, 2002.
Project description:To identify functions that distinguish the posterior and median cells producing fibroin and sericin in the silk gland of Bombyx mori, serial analysis of gene expression (SAGE) profiles from both silk gland regions were analyzed and compared. The construction of a B. mori reference tag collection extracted from a set of 38000 Bombyx EST sequenced from the 3’ side, helped annotating the SAGE libraries. Most of the tags appeared at similar relative concentration in the two libraries except for those corresponding to silk proteins that were found region-specific and highly abundant. Strikingly, besides tags from silk protein mRNAs, 19 tags were found in the class of high abundance in the median cell library, which were absent in the posterior cell tag collection. Except tags from SP1 mRNA, no PSG specific tags were found in the same class of abundance. The analysis of MSG-specific different transcripts led to suggest that middle silk gland cell realizes more diversified functions as those already known, of synthesis and secretion of the silk sericins. EST libraries from 11 silkworm tissues were 3’-sequenced to ensure the identification of the most terminal tag. 37,920 sequences were analyzed on ABI 3700 or 3730XL sequencers. Electrophoregrams were processed with KB Basecaller (3730XL traces) or with PHRED (3700 traces) to obtain the .phd files from which were extracted text sequences and their corresponding quality files in Fasta format (Phd2Fasta, Green and Ewing, 1995; 2002). Vector sequences and bad quality regions were removed with an home made software after identification by Lucy (Chou and Holmes, 2001). Chimera were removed by an home made software and retrotransposon sequences were masked by RepeatMasker (http://repeatmasker.org). The cleaned sequences were clusterized with TGICL package (TIGR) and assembled into contigs with CAP3 (Huang and Madan, 1999). Contigs were identified with Blastn and Blastx on GenBank and SwissProt/TREMBL, respectively. Some clusters, splitted by CAP3 procedure, have been regrouped on the basis of Blastx identity. Identitag (Keime et al., 2004) was used to extract all possible tags (forward and reverse) to create a reference database. Moreover, a quality index is attached to each tag depending to the presense of poly-A, polyadenylation signal and its proximity to 3-prime extremity in the original mRNA sequence. This database was supplemented with the tags extracted from public B. mori sequences (GenBank, Silkbase) with the same software. Tags were extracted from MSG and PSG libraries (from 2304 and 3072 sequenced inserts respectively) with the Sagenhaft software (Beissbarth et al., 2004) then identified and compared with Identitag. The assessment of significant differences among the two libraries was performed by using the Z-test used for comparison of SAGE libraries of different size (Kal et al., 1999). For graphic purpose and to avoid division by zero we used a tag value of 1 for tags that were not detected in MSG or PSG libraries. Since the two SAGE libraries showed up different TAG number, we used the Z-test for comparing the two mRNA populations.
Project description:Juvenile hormone (JH) is produced and secreted by corpora allata (CA) during larval stages. JH biosynthesis from acetyl-CoA includes 13 enzymatic steps. Genes for 10 of those enzymes have been identified from Bombyx mori. It was also reported that they are basically expressed selectively in CA. Genes for the other 3 enzymes were recently reported from other insects, i.e., farnesyl diphosphate pyrophosphatase (FPPP) from Drosophila and farnesol dehydrogenase (FolD) and farnesal dehydrogenase (FalD) from Aedes. In order to reveal the expression profiles of these genes in Bombyx CA and to find other candidate genes involved in JH biosynthesis, we performed a transcriptomic analysis in corpora cardiaca-CA (CC-CA) complexes using a custom-made DNA microarray on which sequences from CC-CA EST libraries and genome-widely predicted genes are loaded. CC-CA complexes vigorously expressed JH-biosynthetic genes identified in Bombyx as well as genes involved in methyl-group metabolism and ribosomal protein genes; this is suitable for JH production. Bombyx counterparts of Drosophila FPPP and Aedes FolD genes, however, showed quite low level of expression. On the other hand, some other genes probably encoding oxidoreductases were expressed highly and selectively in CC-CA complex. Their products might function as FolD and/or FalD in Bombyx.
Project description:As important roles of small RNA pathways, AGO proteins mediate interaction of incorporated small RNAs with their targets. The resolution of AGO associated small RNAs showed a significant landscape of AGO proteins and their binding small RNAs. To characterize small RNAs that associated with BmAGO2 protein in Bombyx mori, the small RNA population associated with BmAGO2 in BmN cells was extracted from the AGO immunoprecipitated complex and the small RNAs between 17nt to 50nt separated by a polyacrylamide gel electrophoresis were subjected to library construction and deep sequencing.The high throughput sequencing yielded a total of 11691441 reads, representing 813,702 unique reads with a abundance from 5731905 to 1.
Project description:A mass spectrometry-based proteomics analysis was performed to study the protein binders of GTSF1L in germ cell culture (BmN4; ovary-derived) of Bombyx mori. Anti-HA pull-downs were performed in BmN4 cells transfected with the HA-BmGtsf1L plasmid or the HA-eGFP control plasmid. Proteins were digested in-gel by trypsin. The resultant peptides were then dimethyl labelled and combined. Peptides were measured on a Q Exactive Plus Orbitrap mass spectrometer.