Rosa sterilis S. D. Shi is an important economic tree in China that produces fruits with high nutritional and medicinal value.  Many of R. sterilis’ organs are covered with different types of trichomes or prickles that directly affect fruit appearance and plant management.  This study used RNA sequencing technology to analyze the transcriptomes of two parts of the inflorescence branch, namely inflorescence stems with flagellated trichomes and pedicels with both flagellated and glandular trichomes.  Comparative transcriptomic analysis showed that many transcription factors (TFs) are potentially involved in the formation and development of trichomes.  The accumulation of RsETC1, a TF of the R3-MYB family, was significantly higher in inflorescence stems than in pedicels; quantitative reverse transcription PCR (qRT-PCR) verified that its expression was significantly higher in inflorescence stems than in pedicels during the first three development stages, indicating its inhibitory action on the initiation of glandular trichomes in R. sterilis.  The mRNA level of RsETC1 accumulated to significantly higher levels in trichomeless tissues than in tissues with trichromes, suggesting that this gene may inhibit the formation of trichomes in R. sterilis.  Over-expression of RsETC1 in Arabidopsis resulted in glabrous phenotypes, and the expression of trichome-related endogenous genes, except for TTG1, was markedly reduced.  In addition, the contents of the phytohormones jasmonic acid (JA), gibberellin A3 (GA₃), and cytokinins (CKs) in pedicels were significantly higher than those in inflorescence stems, and the expression patterns of the genes related to hormone biosynthesis and signal transduction presented consistent responses, suggesting that the transduction of these hormones might be crucial for trichome initiation and development.  These data provide a new perspective for revealing the molecular mechanism of trichome formation in R. sterilis.

Many proteins require assistance from molecular chaperones at various stages to attain correctly folded states and functional conformations during protein synthesis.  In this study, the gene encoding T-complex polypeptide 1 (TCP-1), which belongs to the heat shock protein 60 (HSP60) family, was isolated and characterized from the rice stem borer, Chilo suppressalis, by RACE and qPCR, respectively.  The full-length cDNA of Tcp-1 was 2 144 bp and encoded a 1 635-bp ORF; the deduced translational product contained 545 amino acids with 5´- and 3´-UTRs and an isoelectric point of 5.29.  Cluster analysis confirmed that the deduced amino acid sequence shared high identity (60–99%) with TCP-1 from other insects.  To investigate Tcp-1 expression in response to abiotic stress, qPCR was used to analyze expression levels of Tcp-1 mRNA in C. suppressalis larvae exposed to temperatures ranging from –11 to 43°C.  With respect to heat shock, Tcp-1 expression was higher than the control after a 2-h exposure to 30 and 36°C and declined at 39 and 43°C.  Difference in Tcp-1 expression was observed at temperatures ranging from –11 to 27°C.  qPCR analyses revealed that Tcp-1 expression was the highest in hindgut tissue as compared to heads, epidermis, fat body, foregut, midgut, and malpighian tubules.  Our results indicated that Tcp-1 expression was differentially expressed in C. suppressalis tissues, and was impacted by temperature stress.

Heat shock protein 70 (HSP70) is one of the most important members in the heat shock protein family, and plays important roles in the thermotolerance of insect.  To explore the molecular mechanism of thermotolerance of Frankliniella occidentalis adults, the difference in the expression of HSP70s in F. occidentalis male or female adults under the thermal stress was studied under the laboratory conditions.  Two full length cDNAs of HSP70s gene (Fohsc704 and Fohsc705) were cloned from F. occidentalis by using RT-PCR and RACE.  The genomic sequence was demonstrated by genomic validation, and the position and size of the intron were analyzed by sequence analysis of cDNA.  Real-time PCR was used to analyze the HSP70 expression patterns.  The cDNA of Fohsc704 and Fohsc705 possessed 2 073 and 1 476 bp which encoded 690 and 491 amino acids (aa) with a calculated molecular weight of 75 and 54 kDa, respectively.  Four introns in Fohsc704 and six introns in Fohsc705 protein were found.  However, the HSP70 protein sequences in our study were ended with EKKN and GIFL, which were different from the reported FoHSP70s.  Various expression patterns of Fohsc704 and Fohsc705 were found in both genders of F. occidentalis under thermal stress.  The expression of Fohsc704 and Fohsc705 reached to the highest level at –12 and –8°C in male adults, respectively, and Fohsc705 expressed the highest level at 33°C in female adults.  In conclusion, HSP70s of F. occidentalis in our study are novel heat shock proteins.  There were difference in expression patterns of the two hsc70s in genders of F. occidentalis, and the two HSP70s play important roles in the thermotolerance of F. occidentalis.  

Five genes encoding heat shock proteins (HSPs), Cchsp40, Cchsp60, Cchsp70, Cchsc70 and Cchsp90, were cloned and sequenced from Cotesia chilonis using RT-PCR and RACE.  The cDNA sequences of Cchsp40, Cchsp60, Cchsp70, Cchsc70 and Cchsp90 were 1 265, 2 551, 2 094, 2 297 and 2 635 bp in length, respectively, with a molecular weight (MW) of 39.1, 60.6, 71.45, 70.19 and 82.92 kDa, respectively.  The predicted amino acid sequences of these proteins showed high similarities with published HSPs of other insects in Hymenoptera.  Analysis of genomic DNAs indicated that Cchsp40, Cchsp60, Cchsp70, Cchsc70 and Cchsp90 lacked introns, but Cchsc70 contained an intron.  The results also suggested that CcHSP40 in C. chilonis was the Type II HSP40, CcHSP60 was a member of the mitochondrial HSP60 family, and CcHSP90 was a part of cytoplasmic HSP90A family.  Expression patterns varied in the five Cchsps in response to temperature.  Expression of Cchsp40 and Cchsp60 was induced significantly by cold but not heat stress.  Cchsp70 and Cchsc70 showed similar response to the thermal stress and could be induced by both cold and heat, but their expression levels were consistently lower than that of Cchsp40 and Cchsp60.  Cchsp90 could be induced by heat stress and mild cold, but not cold stress.  In addition, the results demonstrated Cchsc70 might be constitutive and inducible protein that was expressed during normal cell functioning and also up-regulated in response to stressful stimuli while Cchsp70 was solely inducible protein induced by temperature changes.  Overall, results generated from this study could significantly advance the understanding of Cchsps in response to temperature and provide important biological information for C. chilonis insects that reared under different temperatures.  

The function of the 3 040 bp sequence at the upstream translation starting site (ATG) of the ZAG2 gene, isolated from the maize genome, was studied. The sequence analysis showed that the sequence contained a typical class C MADS-box gene regulatory element. The 5´ UTR region of the gene contains a 1 299-bp intron that might have important regulatory functions. To study the sequence function, deletion derivatives of promoter-reporter (uidA) gene fusions were generated and transformed into tobaccos. The GUS staining and fluorescence quantification results showed that the GUS activity was detected only in the third and fourth whorl floral organs of the transgenic tobaccos under driving the promoter including the first intron, while detected in all the organs and was stronger under driving the promoter without the first intron. However, the GUS activity was just detected in one whorl of the fourth or third floral organs under driving of the 35S promoter. These results suggested that the first intron of the ZAG2 gene contains functional regulatory elements, which turned out to be important for gene expression in the heterologous systems. Moreover, the GUS activity was decreased when the reporter gene driven by the promoters with 5´-deletions, respectively, from -1 606 to -951 and -951 to -426 nts, which indicates that positive regulatory elements are present in these two sequence stretches.