Other projects:

Project 1

Project 3

Project 4

fig1

Figure 1: Targets of miR-71 in the Insulin/IGF Signaling and DNA Damage Checkpoint Pathways: Schematic representation and secondary structures of miR-71 binding sites on the 3'UTR of PDK-1, a component of the insulin/IGF signaling pathway, and on the 3'UTR of CDC-25.1, a component of the DNA damage checkpoint pathway. In a miR-71 deletion genetic background (mir-71(n4115)), the mRNA levels of PDK-1 and CDC-25.1 are significantly upregulated specifically in older adult animals (day 10) as compared to wild-type N2 animals as measured by qRT-PCR. Error bars represent standard deviation. Model for molecular and genetic interactions of age-related miRNAs with known aging pathways. Pointed arrows denote positive interaction; blunt arrows denote negative interactions. (Figure adapted from: de Lencastre, Current Biology, 2010).

Project 3:

Stress response and aging pathways regulated by miRNAs.

In our previous research, we have shown that several aging-associated miRNAs genetically interact with components of the DNA damage checkpoint response (DDR) pathway and the insulin signaling (ISS) pathway to mediate longevity and stress resistance (Figure 1). We identified specific genes in these pathways which are likely under the negative regulation of aging-associated genes. Using qRT-PCR and bioinformatic analysis of the 3'UTRs of these genes, we found evidence that miR-71 represses the expression of PDK-1 in the ISS pathway and CDC-25.1 in the DDR pathway. In order to identify novel molecular mechanisms and pathways that underlie the function of miRNAs during aging in C. elegans, we are currently conducting an unbiased search for all possible targets of aging- associated miRNAs through transcriptome profiling and functional genetic screens (Figure 2).


Fig2

Figure 2: We are currently utilizing deep sequencing technologies, such as RNA-seq to evaluate the changes in expression of RNA messages in mutant animals that over-express or have deletions in aging-associated miRNAs, such as miR-71 and miR-239. As miRNAs are canonic negative regulators of gene expression we expect to see that overexpression of these miRNAs will lead to downregulation of candidate miRNA targets genes as shown here. We are currently validating lists of candidate genes identified by these approaches.