Targeting transcriptional regulators to regenerate midbrain dopaminergic axons in Parkinson's disease

Introduction： Parkinson＇s disease （PD） is a chronic, age-re- lated neurodegenerative disorder that affects 1-2% of the population over the age of 65. PD is characterised by the progressive degeneration of nigrostriatal dopaminergic （DA） neurons. This leads to disabling motor symptoms, due to the striatal DA denervation. Despite decades of research, there is still no therapy that can slow, stop or regenerate the dying midbrain DA neurons in PD.

The Regulatory Roles of microRNAs and Associated Target Genes during Early Somatic Embryogenesis in Liriodendron Sino-Americanum

Somatic cells respond to considerable stress,and go through a series of phytohormone pathways,then forming an embryo.The developmental process is recorded as somatic embryogenesis(SE).One of the key components regulating SE are the microRNAs(miRNAs).Despite previous studies,it is still not clear exactly how miRNAs exert their function of regulating targets during conditionally activated early SE.Here,we use Liriodendron sino-americanum as a model system and perform a combined analysis of microfluidic chips and degradome sequencing to study this process.We identified a total of 386 conserved miRNAs and 153 novel miRNAs during early SE.According to the ANOVA test,239 miRNAs showed 12 distinct expression patterns.Through degradome sequencing,419 targets and 198 targets were identified for 136 known miRNAs and 37 novel miRNAs,respectively.Gene Ontology(GO)and metabolism pathway enrichment analysis revealed that these targets were significantly involved in oxidation-reduction processes,calmodulin-mediated signal transduction pathways and carbohydrate metabolism.The genes that were related to stress responses,phytohormone pathways and plant metabolism were identified within the targets of miR319,miR395,miR408,miR472,miR482,miR390,miR2055,miR156,miR157,miR171,miR396,miR397,miR529,miR535 and miR159.According to promoter analysis,various cis-acting elements related to plant growth and development,phytohormones response and stress response were present in the promoter of the miRNAs.The differential expression patterns of 11 miRNA-target modules were confirmed by real-time quantitative PCR.The study demonstrated that the miRNA plays an important role in the early SE process by regulating its target and then participating in carbohydrate metabolism and stress response.It also provided a valuable resource for further research in determining the genetic mechanism of SE,and then facilitating breeding programs on plants.

Identification and expression profiling of Vigna mungo microRNAs from leaf small RNA transcriptome by deep sequencing

MicroRNAs （miRNAs） represent a class of small non-coding RNA molecules that play a crucial role in post- transcriptional gene regulation. Several conserved and species-specific miRNAs have been characterized to date, predominantly from the plant species whose genome is well characterized. However, information on the variability of these regulatory RNAs in economically important but genetically less characterized crop species are limited. Vigna mungo is an important grain legume, which is grown primarily for its protein-rich edible seeds, miRNAs from this species have not been identified to date due to lack of genome sequence information. To identify miRNAs from V. mungo, a small RNA library was constructed from young leaves. High- throughput IIlumina sequencing technology and bioinformat- ic analysis of the small RNA reads led to the identification of 66 miRNA loci represented by 45 conserved miRNAs belonging to 19 families and eight non-conserved miRNAs belonging to seven families. Besides, 13 novel miRNA candidates in V. mungo were also identified. Expressior patterns of selected conserved, non-conserved, and nove miRNA candidates have been demonstrated in leaf, stem, ant root tissues by quantitative polymerase chain reaction, ant potential target genes were predicted for most of the conserved miRNAs. This information offers genomic resour ces for better understanding of miRNA mediated post transcriptional gene regulation.