De Novo transcriptome assembly and differential expression analysis of catharanthus roseus in response to salicylic acid.

The anti-cancer vinblastine and vincristine alkaloids can only be naturally found in periwinkle (Catharanthus roseus). Both of these alkaloids' accumulations are known to be influenced by salicylic acid (SA). The transcriptome data to reveal the induction effect (s) of SA, however, seem restricted at this time. In this study, the de novo approach of transcriptome assembly was performed on the RNA-Sequencing (RNA-Seq) data in C. roseus. The outcome demonstrated that SA treatment boosted the expression of all the genes in the Terpenoid Indole Alkaloids (TIAs) pathway that produces the vinblastine and vincristine alkaloids. These outcomes supported the time-course measurements of vincristine alkaloid, the end product of the TIAs pathway, and demonstrated that SA spray had a positive impact on transcription and alkaloid synthesis. Additionally, the abundance of transcription factor families including bHLH, C3H, C2H2, MYB, MYB-related, AP2/ ERF, NAC, bZIP, and WRKY suggests a role for a variety of transcription families in response to the SA stimuli. Di-nucleotide and tri-nucleotide SSRs were the most prevalent SSR markers in microsatellite analyses, making up 39% and 34% of all SSR markers, respectively, out of the 77,192 total SSRs discovered.

The expression of Terpenoid Indole Alkaloid (TIAs) pathway genes in Catharanthus roseus in response to salicylic acid treatment.

Vinblastine and vincristine are two important anti-cancer drugs that are synthesized by the Terpenoid Indole Alkaloids (TIAs) pathway in periwinkle (Catharanthus roseus). The major challenge in the pharmaceutical industry is the low production rate of these Alkaloids. TIA pathway is affected by elicitors, such as salicylic acid (SA). This study aimed to investigate the expression pattern of some key genes in TIAs pathway under SA treatment. Foliar application of SA (0.01 and 0.1 mM) was used and leaves samples were taken at 0, 12, 18, 24 and 48 h after the treatment. qRT-PCR was used to investigate the expression pattern of Chorismate mutase (Cm), tryptophan decarboxylase (Tdc), Geraniol-10-hydroxylase (G10h), Secologanin synthase (Sls), Strictosidine synthase (Str), Desacetoxyvindoline-4-hydroxylase (D4h) and Deacetylvindoline-4-O-acetyltransferase (Dat) genes, following the SA treatment. The results of this experiment showed that transcript levels of Tdc, G10h, Sls, Str, D4h and Dat genes were significantly up-regulated in both SA concentration treatments. Furthermore, the highest transcript levels of Dat was observed after 48 h of the SA treatments. qRT-PCR results suggests that SA induces transcription of major genes involved in Alkaloids biosynthesis in Catharanthus roseus. It can be concluded that up-regulation of Tdc, G10h, Sls, Str, D4h and Dat genes can result in a higher production rate of Vinblastine and vincristine Alkaloids.

Expression pattern of ABCDE model genes in floral organs of bolting garlic clone.

A correct understanding of the ABCDE model genes expression, especially genes involved in the development of the reproductive floral organs, in bolting and fertile garlic clones improves the process of its fertilization and breeding programs. Therefore, Real-Time PCR was employed to evaluate the temporal and spatial expression patterns of some floral organ identity genes in the inflorescence and different floret organs in the two stages of green and purple florets of bolting garlic clone. Relative expression of the studied genes, except AsSTK, in the mature inflorescence increased significantly during the early stages of initiation and differentiation of floral organs. Relative expression of the AsAP1 in the tepal and carpel, and AsAP2 in the tepal, stamen and carpel increased significantly. The highest relative expression levels of the AsAP1 and AsAP2 were found in the tepal of green florets and in the carpel of purple florets, respectively. AsAP3 and AsPI expression increased significantly in the stamen and carpel, and the highest relative expression of these two genes were observed in the green floret tepal. Relative expression of the AsAG increased significantly only in the reproductive floral organs and decreased significantly both in the carpel and stamen at floret maturity. The AsSEP1, 3 were expressed in all floral organs, but the AsSTK was only expressed in the carpel and its relative expression increased significantly at floret maturity. Finally, since considerable expression levels of the above genes were observed in the floral organs, these genes seem to be influential in the formation of floral organs in bolting garlic.

Transient expression of recombinant tissue plasminogen activator (rt-PA) gene in cucurbit plants using viral vector.

OBJECTIVE: To use a transient expression system to express a truncated human tissue plasminogen activator (K2S) gene in cucurbit plants. RESULTS: The recombinant tissue plasminogen activator protein (K2S form) was expressed in active form in cucurbit plants. Its molecular weight was 43 kDa. The plant-derived rt-PA was determined using goat anti-rabbit antibody by western blotting. Among the infected lines, the highest expression of rt-PA was 62 ng/100 mg per leaf tissue as measured by ELISA. The enzymatic activity of the plant-derived rt-PA was 0.8 IU/ml. CONCLUSIONS: The K25 form of rt-PA was expressed for the first time using the viral expression system. Plant-derived rt-PA showed similar potency to commercially-available PA.

Proteomic insights into intra- and intercellular plant-bacteria symbiotic association during root nodule formation.

Over the last several decades, there have been a large number of studies done on the all aspects of legumes and bacteria which participate in nitrogen-fixing symbiosis. The analysis of legume-bacteria interaction is not just a matter of numerical complexity in terms of variants of gene products that can arise from a single gene. Bacteria regulate their quorum-sensing genes to enhance their ability to induce conjugation of plasmids and symbiotic islands, and various protein secretion mechanisms; that can stimulate a collection of chain reactions including species-specific combinations of plant-secretion isoflavonoids, complicated calcium signaling pathways and autoregulation of nodulation mechanisms. Quorum-sensing systems are introduced by the intra- and intercellular organization of gene products lead to protein-protein interactions or targeting of proteins to specific cellular structures. In this study, an attempt has been made to review significant contributions related to nodule formation and development and their impacts on cell proteome for better understanding of plant-bacterium interaction mechanism at protein level. This review would not only provide new insights into the plant-bacteria symbiosis response mechanisms but would also highlights the importance of studying changes in protein abundance inside and outside of cells in response to symbiosis. Furthermore, the application to agriculture program of plant-bacteria interaction will be discussed.