Analysis of 41 kb of the DNA sequence from the right arm of chromosome II of Schizosaccharomyces pombe

Identification and validation of reference genes for gene expression analysis in Aphidius gifuensis (Hymenoptera: Aphidiidae)

Reference genes have been utilized in estimating gene expression levels using quantitative reverse transcriptase-quantitative polymerase chain reaction (qRT-PCR) analysis. Aphidius gifuensis Ashmaed is one of the most widely used biological control agents for aphids. The biological properties of this species have been studied in detail, and current investigations are focused on elucidating the regulatory mechanisms in its host However, the appropriate reference genes for target gene expression studies have not been identified. In this study, the expression profiles of 12 candidate reference genes were evaluated under different experimental conditions(development stage, sex, tissue type, diet) by using dedicated algorithms, including geNorm, Normfinder, BestKeeper, and ΔCt. In addition, RefFinder was used to rank the overall stability of the candidate genes. Finally, we recommend three optimal reference genes for the normalization of qRT-PCR data in the presence of specific variables, which include ACTB, RPL13, and PPI for different developmental stages; RPS18, ACTB, and RPL13 for sexes; RPL13, PRII3, and RPS18 in different tissue types; and RPL13, RPL27, and ACTB in diverse diets. The present study has identified optimal reference genes that could be used in estimating the expression levels of specific genes under these conditions following the Minimum Information for publication of Quantitative real-time PCR Experiments (MIQE) guidelines, which would facilitate in advancements in functional genomics research on A. gifuensis.

Comprehensive evaluation of candidate reference genes for gene expression studies in Lysiphlebia japonica (Hymenoptera: Aphidiidae) using RT-qPCR

Lysiphlebia japonica (Ashmead) is a predominant parasitoid of cotton-melon aphids in the fields of northern China with a proven ability to effectively control cotton aphid populations in early summer. For accurate normalization of gene expression in L. japonica using quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR), reference genes with stable gene expression patterns are essential. However, no appropriate reference genes is L. japonica have been investigated to date. In the present study, 12 selected housekeeping genes from L. japonica were cloned. We evaluated the stability of these genes under various experimental treatments by RT-qPCR using four independent (geNorm, NormFinder, BestKeeper and Delta Ct) and one comparative (RefFinder) algorithm. We identified genes showing the most stable levels of expression: DIMT, 18S rRNA, and RPL13 during different stages; AK, RPL13, and TBP among sexes; EF1A, PPI, and RPL27 in different tissues, and EF1A, RPL13, and PPI in adults fed on different diets. Moreover, the expression profile of a target gene (odorant receptor 1, OR1) studied during the developmental stages confirms the reliability of the chosen selected reference genes. This study provides for the first time a comprehensive list of suitable reference genes for gene expression studies in L. japonica and will benefit subsequent genomics and functional genomics research on this natural enemy.

Characterization of a chaperone ClpB homologue of Paracoccidioides brasiliensis

We report the cloning and sequence analysis of a genomic clone encoding a Paracoccidioides brasiliensis ClpB chaperone homologue (PbClpB). The clpb gene was identified in a lambda Dash II library. Sequencing of Pbclpb revealed a long open reading frame capable of encoding a 792 amino acid, 87.9 kDa protein, pI of 5.34. The predicted polypeptide contains several consensus motifs of the ClpB proteins. Canonical sequences such as two putative nucleotide-binding sites, chaperonins ClpA/B signatures and highly conserved casein kinase phosphorylation domains are present. ClpB is 69% to 49% identical to members of the ClpB family from several organisms from prokaryotes to eukaryotes. The transcript of PbclpB was detected as a mRNA species of 3.0 kb, preferentially expressed in the yeast parasitic phase of the fungus. A 89 kDa protein was also detected in yeast cells of P. brasiliensis.