Project description:The construction of complex gene regulatory networks requires both inhibitory and up-regulatory modules. However, the vast majority of RNA-based regulatory “parts” are inhibitory. Using a synthetic biology approach combined with SHAPE-Seq, we explored the regulatory effect of RBP-RNA interactions in bacterial 5’-UTRs. By positioning a library of RNA hairpins upstream of a reporter gene and co-expressing them with the matching RBP, we observed a set of regulatory responses, including translational stimulation, translational repression, and cooperative behavior. Our combined approach revealed three distinct states in-vivo: in the absence of RBPs, the RNA molecules can be found either in a molten state that is amenable to translation, or a structured phase that inhibits translation. In the presence of RBPs, the RNA molecules are in a semi-structured phase with partial translational capacity. Our work provides new insight into RBP-based regulation and a blueprint for designing complete gene regulatory circuits at the post-transcriptional level.
Project description:down/up regulation of nad biosynthesis in arabidopsis and role of l-aspartate oxidase-Down/up regulation of NAD biosynthesis in Arabidopsis : role of L-Aspartate oxidase
Project description:We sequenced mRNAs from bone borrow derived macrophages derived from the control (WT) and RBP-J conditional knockout mice (RBP-J KO; Rbpj f/f;LysM cre).
Project description:RBP-J is a master transcriptional factor of Notch signaling, which plays important roles in developmental processes as well as regulating macrophage-mediated inflammatory responses. However, the regulation of RBP-J on miRNAs are less studied. So we sequenced microRNAs from BMDMs derived from the LyZ2 Cre control (WT) and RBP-J conditional knockout mice (RBP-J KO; Rbpjf/f LyZ2 Cre) to address the roles of RBP-J on regulating miRNAs in macrophages.
Project description:A T-DNA insertion within RBP-L 3’UTR resulted in 10-25% expression level of RBP-L gene compared to wild-type. The reduced expression of RBP-L caused partial mis-localization of glutelin and prolamine RNAs and conferred other general growth defects including dwarfism, late flowering and smaller seeds. Transcriptome analysis showed that RBP-L knockdown greatly affected the expression of prolamine family genes and many genes invovled in essential biological pathways during plant development.
Project description:RNA binding proteins (RBPs) regulate gene expression through several post-transcriptional mechanisms. The broadly expressed HuR/ELAVL1 RBP is important for proper function of multiple cell types in the immune system, and has been proposed to positively control the expression of cytokine and other mRNAs upon activation by regulating their 3′ UTRs. However, this mechanism has not been previously dissected in stable cellular settings. In this study, HuR demonstrated strong anti-apoptotic and activation roles in the Jurkat T cell line. Detailed transcriptomic analysis of HuR knockout cells revealed a substantial negative impact on the activation program, coordinately preventing the expression of several gene categories related to the immune response, including all cytokines. Measurements of IL-2 production showed a significant defect in knockout cells, which was rescued upon reintroduction of HuR. Interestingly, the mechanism of HuR regulation did not involve control of the cytokine 3′ UTRs: HuR knockout did not affect the activity of several cytokine 3′ UTR reporters in 293 cells. Similarly, HuR had no effect on the regulation of IL-2 and TNF 3′ UTRs in resting or activated Jurkat cells. Instead, impaired cytokine production corresponded with defective induction of the IL-2 promoter upon activation. Accordingly, upregulation of the master transcription factor NFATC1 upon activation was also impaired in HuR KOs, without effects on its 3′ UTR. Together, these results indicate that HuR controls cytokine production through coordinated upstream pathways, and that additional mechanisms must be considered in investigating its function.
Project description:Upon detection of a pathogen, the innate immune system triggers signaling events leading to the transcription of mRNAs that encode for pro-inflammatory and anti-microbial effectors. RNA-binding proteins (RBPs) interact with these functionally critical mRNAs and temporally regulate their fates at the post-transcriptional level. One such RBP is ELAVL1, which is known to bind to introns and 3’UTRs. While significant progress has been made in understanding how ELAVL1 regulates mRNAs, how its target repertoire and binding affinity changes within an immunological context remains poorly understood. Here, we overlap four distinct high-throughput approaches to define its cell-type and context-dependent targets and determine its regulatory impact during immune activation. ELAVL1 overwhelmingly binds to intronic sites in a naïve state, but during an innate immune response, ELAVL1 targets the 3’UTR binding both previously and newly expressed mRNAs. We find that ELAVL1 mediates the RNA stability of genes that regulate the pathways involved in pathogen sensing and cytokine production. Our findings reveal the importance of examining RBP regulatory impact under dynamic transcriptomic events to best understand their post-transcriptional regulatory roles within specific biological circuitries.
Project description:rs13_01_lao - down/up regulation of nad biosynthesis in arabidopsis and role of l-aspartate oxidase - Study of the biosynthesis of NAD in Arabidopsis. Involvment of L-Aspartate oxidase gene using T-DNA mutant (SAIL1145_B10) and overexpressor lines (promotor 35S, vector PCW162) at the same developmental stage (12 leaves) - Study of the biosynthesis of NAD in Arabidopsis. Involvment of L-Aspartate oxidase gene using T-DNA mutant (SAIL1145_B10) and overexpressor lines (promotor 35S, vector PCW162) at the same developmental stage (12 leaves)
Project description:Much of posttranscriptional mRNA regulation occurs through cis-acting sequences in mRNA 3´ untranslated regions (UTRs), which interact with specific proteins and ribonucleoprotein complexes that modulate translation, mRNA stability and subcellular localization. Studies in Caenorhabditis elegans have revealed indispensable roles for 3´UTR-mediated gene regulation, yet most C. elegans genes have lacked annotated 3´UTRs. Here we describe a high-throughput method to reliably identify 3´ ends of polyadenylated RNAs. This method, called poly(A)-position profiling by sequencing (3P-Seq), was used to determine the UTRs of C. elegans. Compared to standard methods also recently applied to C. elegans UTRs, 3P-Seq identified 8775 additional UTRs while excluding thousands of shorter UTR isoforms that do not appear to be authentic. Analysis of this expanded and corrected dataset indicated that the high A/U content of C. elegans 3´UTRs facilitated genome compaction, since the elements specifying cleavage and polyadenylation, which are A/U-rich, can more readily emerge in A/U rich regions. Indeed, 30% of the protein-coding genes have mRNAs with alternative, partially overlapping end regions that generate another 10,000 cleavage and polyadenylation sites that had gone largely unnoticed and represent potential evolutionary intermediates of progressive UTR shortening. Moreover, a third of the convergently transcribed genes utilize palindromic arrangements of bidirectional elements to specify UTRs with convergent overlap, which also contributes to genome compaction by eliminating regions between genes. Although nematode 3´UTRs have median length only one-sixth that of mammalian 3´UTRs, they have twice the density of conserved microRNA sites, in part because additional types of seed-complementary sites are preferentially conserved. These findings reveal the influence of cleavage and polyadenylation on the evolution of genome architecture and provide resources for studying posttranscriptional gene regulation. Nine samples (10 sequencing runs) from various mixed and specific stages of wild-type Caenorhabditis elegans and glp-4 mutant adults.