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Modification of lipid composition in the mesocarp tissue of oil palm involves genetic manipulation of multiple genes. More than one mesocarp-preferential promoter is necessary for the expression of individual transgenes in the same plant to obviate transcriptional gene silencing. This study aimed to identify genes that are preferentially expressed in the mesocarp tissue and characterize selected candidate mesocarp-preferential promoters. Ten transcripts that were preferentially expressed in the mesocarp tissue were identified from the analysis of 82 transcriptome datasets of 12 different oil palm tissues. The expression of two candidate genes, MSP-C1 and MSP-C6 , was verified to be preferentially expressed in the mesocarp tissues and shown to have a low expression level in non-mesocarp tissues by reverse transcription quantitative real-time PCR (RT-qPCR). MSP-C6 promoter fragments of different lengths were transformed into tomato plants for further characterization. Both unripe and ripe fruits of transgenic tomato plants transformed with a construct harboring the MSP-C6-F1 (2014 bp) promoter were shown to have high beta-glucuronidase (GUS) activities. The findings of this study suggest the potential applications of the MSP-C6 promoter as a molecular tool for genetic engineering of novel traits in fruit crops. • Ten mesocarp-preferential transcripts were identified from the analysis of 82 oil palm transcriptome datasets. • Two candidate genes were verified to be preferentially expressed in the oil palm mesocarp tissues. • The MSP-C6-F1 (2014 bp) promoter fragment was shown to be able to drive preferential gene expression in tomato fruits. • Characterization of mesocarp-specific promoters contribute to future genetic manipulation of oil synthesis in oil palm. [ABSTRACT FROM AUTHOR]

Proline-rich extensin-like receptor kinases (PERKs) play a crucial role in a wide range of biological processes in plants. In model plants like Arabidopsis, the PERK gene family has been well investigated. Conversely, no information available on the PERK gene family and their biological functions largely remained unknown in rice. This study analyzed the basic physicochemical properties, phylogeny, gene structure, cis-acting elements, Gene ontology (GO) annotation and protein-protein interaction of OsPERK gene family members using various bioinformatics tools based on the whole-genome data of O. sativa. Thus, in this work, 8 PERK genes in rice were identified, and their roles in plant development, growth, and response to various stresses were studied. A phylogenetic study revealed that OsPERKs are grouped into seven classes. Chromosomal mapping also displayed that 8 PERK genes were unevenly distributed on 12 chromosomes. Further, the prediction of subcellular localization indicated that OsPERKs were mainly located at the endomembrane system. Gene structure analysis of OsPERKs has shown a distinctive evolutionary path. In addition, synteny analysis exhibited the 40 orthologous gene pairs in Arabidopsis thaliana, Triticum aestivum, Hordeum vulgare and Medicago truncatula. Furthermore, Ka to Ks proportion shows that most OsPERK genes experienced resilient purifying selection during evolutionary processes. The OsPERK promoters contained several cis-acting regulatory, which are crucial for plant development processes, phytohormone signaling, stress, and defense response. Moreover, the expression pattern of OsPERK family members showed differential expression patterns in different tissues and various stress conditions. Taken together, these results provide clear messages for a better understanding the roles of OsPERK genes in various development stages, tissues, and multifactorial stress as well as enriched the related research of OsPERK family members in rice. • In this work, 8 PERK genes were identified, and their roles in plant growth and development and response to various stresses were studied in rice. • Phylogenetic analysis revealed that OsPERKs are grouped into seven classes. In addition, gene structure analysis of OsPERKs has shown a distinctive evolutionary path. • Further, Synteny analysis exhibited the 40 orthologous gene pairs in Arabidopsis thaliana, Triticum aestivum, Hordeum vulgare and Medicago truncatula. • Moreover, Ka to Ks proportion shows that most OsPERK genes experienced a strong purifying selection during evolutionary processes. • The OsPERK promoters contained several cis-acting regulatory, which are crucial for plant development processes, phytohormone signaling, stress, and defense response. • The expression pattern of OsPERK family members showed differential expression patterns in different tissues and various stress conditions. [ABSTRACT FROM AUTHOR]

An array of external factors, an important one being temperature, decide the fate of survival in a microbe. The ability of microbes to sense external cues and to regulate the expression of genes accordingly is critical for its likely survival. Among a myriad of cellular defence mechanisms, a strategy to recuperate stress involves RNA regulatory elements. RNAs own a repertoire of functions in a cell as messengers, for transfer or as a component of ribosomes. A shift from its indigenous role is as regulators of gene expression, where in the cis-encoded RNA termed as "RNA Thermometers" play a pivotal role in translational level of gene expression. In this paper, we review the occurrence, the different types and molecular mechanism of gene regulation by RNATs, with a special focus limited to the domain Bacteria. We discuss the role of RNATs in mediating expression of temperature-responsive genes like heat shock/cold attributing in heat/cold shock response and a cascade of virulence genes to evade host defence mechanisms. • Bacterial RNATs occurrence and its different types. • Bacterial RNATs molecular mechanism of gene regulations. • Role of RNATs in mediating expression of temperature responsive genes and genes for virulence. • Role of RNATs in synthetic biology. [ABSTRACT FROM AUTHOR]

Abstract: Artemisinin, an antimalarial endoperoxide sesquiterpene, is synthesized in glandular trichomes of Artemisia annua L. A number of other enzymes of terpene metabolism utilize intermediates of artemisinin biosynthesis, such as isopentenyl and farnesyl diphosphate, and may thereby influence the yield of artemisinin. In order to study the expression of such enzymes, we have cloned the promoter regions of some enzymes and fused them to β-glucuronidase (GUS). In this study, we have investigated the expression of the monoterpene synthase linalool synthase (LIS) using transgenic A. annua carrying the GUS gene under the control of the LIS promoter. The 652bp promoter region was cloned by the genome walker method. A number of putative cis-acting elements were predicted indicating that the LIS is driven by a complex regulation mechanism. Transgenic plants carrying the promoter-GUS fusion showed specific expression of GUS in T-shaped trichomes (TSTs) but not in glandular secretory trichomes, which is the site for artemisinin biosynthesis. GUS expression was observed at late stage of flower development in styles of florets and in TSTs and guard cells of basal bracts. GUS expression after wounding showed that LIS is involved in plant responsiveness to wounding. Furthermore, the LIS promoter responded to methyl jasmonate (MeJA). These results indicate that the promoter carries a number of cis-acting regulatory elements involved in the tissue-specific expression of LIS and in the response of the plant to wounding and MeJA treatment. Southern blot analysis indicated that the GUS gene was integrated in the A. annua genome as single or multi copies in different transgenic lines. Promoter activity analysis by qPCR showed that both the wild-type and the recombinant promoter are active in the aerial parts of the plant while only the recombinant promoter was active in roots. Due to the expression in TSTs but not in glandular trichomes, it may be concluded that LIS expression will most likely have little or no effect on artemisinin production. [Copyright &y& Elsevier]

Abstract: Degeneration of the dopaminergic neurons of the substantia nigra is a hallmark of Parkinson’s disease. To facilitate the study of the differentiation and maintenance of this population of dopaminergic neurons both in vivo and in vitro, we generated a knock-in reporter line in which the yellow fluorescent protein (YFP) replaced the first exon and the first intron of the tyrosine hydroxylase (TH) gene in one allele by homologous recombination. Expression of YFP under the direct control of the entire endogenous 5′ upstream region of the TH gene was predicted to closely match expression of TH from the wild type allele, thus marking functional dopaminergic neurons. We found that YFP was expressed in dopaminergic neurons differentiated in vitro from the knock-in mouse embryonic stem cell line and in dopaminergic brain regions in knock-in mice. Surprisingly, however, YFP expression did not overlap completely with TH expression, and the degree of overlap varied in different TH-expressing brain regions. Thus, the reporter gene did not identify functional TH-expressing cells with complete accuracy. A DNaseI hypersensitivity assay revealed a cluster of hypersensitivity sites in the first intron of the TH gene, which was deleted by insertion of the reporter gene, suggesting that this region may contain cis-acting regulatory sequences. Our results suggest that the first intron of the rodent TH gene may be important for accurate expression of TH. [Copyright &y& Elsevier]

• A total of 112 PLA genes and their specific properties to abiotic stress response identified in soybean genome. • Tandem and segmental duplication events accounted for 33 and 55.6 % expansion of PLAs in soybean genome, respectively. • Two paralog genes (GmpPLA-IIε & GmpPLA-IIζ) modulate soybean response to flooding, drought, phosphorus and iron-deficient conditions. Phospholipases A (PLAs) in plants play a crucial role in growth and development, as well as in response to biotic/abiotic stresses. To-date, there has not been any well documented, systematic analysis and comprehensive study of PLAs multigene family in soybean. Therefore, we conducted genome-wide characterization of PLAs in soybean (GmPLAs). Moreover, two paralog genes, GmpPLA-IIε & GmpPLA-IIζ, were knock-out by CRISPR/Cas9 (Clustered regular interspaced short palindromic repeat/CRISPR-associated protein9) technology to study their modulating role in soybean response to multiple abiotic stresses. A total 112 GmPLAs were identified in soybean genome comprising 78 PLA 1 , 29 patatin-like PLAs and 5 secretory sPLA 2. Tandem and segmental duplication events accounted for expansion of PLAs in soybean genome. Some of the mutant lines exhibited superior performance under flooding and drought conditions. Also, the knock-out of the two paralog genes individually or simultaneously disturbed the root's response to a phosphorus-deficient environment relative to the wild type. All the mutants performed better under iron deficient condition compared to the wild type. Our study suggests that PLAs in soybean have diverse physiological and regulatory roles in abiotic stress response and tolerance. The mutants would be useful genetic materials to unravel molecular mechanism underlying soybean response to multiple abiotic stress conditions. [ABSTRACT FROM AUTHOR]