Crockettwells4593
Typical plant terpene synthases (TPSs) are responsible for the production of terpenes, a major class of plant secondary metabolites. However, various nonseed plants also harbor genes encoding microbial terpene synthase-like (MTPSL) enzymes. Here, a scan of 31 ferns transcriptomes revealed 40 sequences putatively encoding MTPSLs. Two groups of sequences were recognized based on the key conserved motifs. Four representative genes were isolated from each of the four species Adiantum capillus-veneris, Cyclosorus parasiticus, Drynaria bonii and Microlepia platyphylla. Following their heterologous expression in E. coli, the recombinant proteins were tested for monoterpene synthase and sesquiterpene synthase activity. These enzymatic products were typical monoterpenes and sesquiterpenes that have been previous shown to be generated by classical plant TPSs when provided with GPP and FPP as substrates. Subcellular localization experiments in the leaf epidermis of Nicotiana benthamiana and onion (Allium cepa) inner epidermal cells indicated that AcMTPSL1 and DbMTPSL were deposited in both the cytoplasm and nucleus, whereas CpMTPSL1 and MpMTPSL were localized in the cytoplasm, chloroplasts and nucleus. AcMTPSL1 was up-regulated in plants exposed to methyl jasmonate treatment, suggesting a role for this gene in host defense. see more This study provides more information about the catalytic function of MTPSLs in nonseed plants and for the first time, the subcellular localization of MTPSLs was experimentally characterized.The transcriptomic response of plants to salinity stress is regulated in part by epigenetic alterations to gene promoter sequences. The transcription factor MsMYB4 is an important component of the response of alfalfa to salinity stress, but the involvement of epialleles of its encoding gene has not as yet been explored. Here, the MsMYB4 promoter was isolated using a genome walking approach in order to perform a deletion analysis to identify the region harboring the elements required for its stress inducibility. The analysis showed that these reside in the sequence lying between 739 and 336 nt up stream of the MsMYB4 translation start codon. The methylation status of the sequence around the MsMYB4 translation start site was altered by the imposition of salinity stress. The activation of MsMYB4 was associated with an increased level of histone H3K4 trimethylation and H3K9 acetylation in specific regions of the promoter sequence. Our results suggest a critical role for MsMYB4's activation by DNA methylation and/or histone modifications in response to salinity stress in alfalfa.4-Coumarate-CoA ligase (4CL) is an important branch point in the phenylpropane pathway and plays important roles in plant growth and development. In this study, the 4CL2 gene from Fraxinus mandshurica (designated Fm4CL2) was identified and isolated. Sequence analysis revealed that Fm4CL2 is a type I 4CL gene involved in lignin biosynthesis. Analysis of cell wall components revealed that Fm4CL2-overexpressing (OE-Fm4CL2) tobacco showed increased lignin content (by 58.9%) and decreased hemicellulose content (by 41.2%). Detection of small-molecule metabolites in the lignin pathway revealed that coumaric acid content decreased by 48% and coniferyl alcohol content increased by 250% compared with the control values. Compared with wild type, OE-Fm4CL2 tobacco showed increased xylem cell layer number (by 120%) and cell wall thickness (by 54.5%). Under osmotic stress, transgenic tobacco showed higher growth than wild-type tobacco. The germination rate of transgenic tobacco was higher than that of wild type. Reactive oxygen species accumulation and malondialdehyde content were significantly lower in transgenic tobacco than in wild type. Under drought, the expression of stress-related genes was higher in 35S-Fm4CL2-infected Fraxinus mandshurica plants than in control plants. These results indicate that Fm4CL2 overexpression can enhance drought and osmotic stress tolerance of plants.The ability to move in synchrony with a perceived regular beat in time is essential for humans to interact with environments in an anticipatory manner, and the basal ganglia have been shown to be preferentially involved in beat processing. Auditory beats are often adopted in assessing the sensorimotor deficiency of patients with Parkinson's disease (PD), which is characterized by basal ganglia dysfunction. Whereas beat synchronization has long been considered to be specific to the auditory modality, recent studies employing moving instead of static visual stimuli have shown comparable synchronization performances of auditory and visual beats. Here, we show that compared with control subjects, synchronization stability of PD patients significantly decreased for beats composed of visual contracting rings but not for beats consisting of auditory tones or static visual flashes. The results revealed specific impairment of visual beat synchronization in PD. Considering the common experience of visuomotor interactions in daily lives of PD patients, the present finding emphasizes the importance of evaluation of visuomotor timing deficiency in PD by employing moving visual stimuli that have ecological relevance.
Prodromal non-motor symptoms precede, often by decades, motor signs and diagnosis of Parkinson's disease. It is however still uncertain if cognitive changes belong to the spectrum of non-motor prodromal Parkinson's disease. Thanks to the very long-term follow-up of the PAQUID population-based cohort, we assessed trajectories of cognitive complaints and functioning over a 13-year period before the diagnosis of late onset Parkinson's disease.
This study relies on a matched nested case-control sample selected from the cohort. Of the 3777 initial subjects of the cohort, 43 developed incident Parkinson's disease over the follow-up. The mean age at diagnosis was 78.0 (standard deviation=5.8) years and 46.5% were men. These cases were matched to 86 elderly control subjects. Scores of different cognitive domains, daily function, and depressive symptoms were described throughout the follow-up using mixed-effects models.
No significant global cognitive decline preceded the diagnosis of late onset Parkinson's disease.