Analysis Of RNA Metabolism Research Articles

Function analysis of RNase E in the filamentous cyanobacterium Anabaena sp. PCC 7120

RNase E is an endoribonuclease and plays a central role in RNA metabolism. Cyanobacteria, as ancient oxygen-producing photosynthetic bacteria, also contain RNase E homologues. Here, we introduced mutations into the S1 subdomain (F53A), the 5′-sensor subdomain (R160A), and the DNase I subdomain (D296A) according to the key activity sites of Escherichia coli RNase E. The results of degradation assays demonstrated that Asp296 is important to RNase E activity in Anabaena sp. PCC 7120 (hereafter PCC 7120). The docking model of RNase E in PCC 7120 (AnaRne) and RNA suggested a possible recognition mechanism of AnaRne to RNA. Moreover, overexpression of AnaRne and its N-terminal catalytic domain (AnaRneN) in vivo led to the abnormal cell division and inhibited the growth of PCC 7120. The quantitative analysis showed a significant decrease of ftsZ transcription in the case of overexpression of AnaRne or AnaRneN and ftsZ mRNA could be directly degraded by AnaRne through degradation assays in vitro, indicating that AnaRne was related to the expression of ftsZ and eventually affected cell division. In essence, our studies expand the understanding of the structural and functional evolutionary basis of RNase E and lay a foundation for further analysis of RNA metabolism in cyanobacteria.

Analysis of RNA Metabolism in Fission Yeast.

Here we focus on the biogenesis and function of messenger RNA (mRNA) in fission yeast cells. Following a general introduction that also briefly touches on other classes of RNA, we provide an overview of methods used to analyze mRNAs throughout their life cycles.

Analysis of RNA metabolism in peripheral WBCs of TDP-43 KI mice identifies novel biomarkers of ALS

Diagnostic biomarkers for amyotrophic lateral sclerosis (ALS) have yet to be identified. One of the causes of neuronal cell death in neurodegenerative diseases is abnormal RNA metabolism, although the mechanisms by which this occurs are unclear. Detection of abnormal RNA metabolism in white blood cells (WBCs) could lead to a new biomarker of ALS onset. TAR DNA-binding protein 43kDa (TDP-43) is an RNA-binding protein that regulates RNA metabolism. We previously developed a mouse model of ALS that exhibits adult-onset motor dysfunction; these mutant TDP-43 knock in (KI) mice heterozygously express mutant human TDP-43 (A382T or G348C). In the present study, we examined TDP-43 mRNA levels in WBCs of KI mice and found that A382T mutant mRNA is significantly higher than G348C. Our results suggest that each mutant TDP-43 induces distinct RNA metabolism, and that the expression of total TDP-43 alone in WBC is not suitable as an ALS biomarker. To identify additional candidates, we focused on survival and apoptosis-related factors and examined their mRNA metabolism in WBCs. mRNA levels of both Smn1 and Naip5 correlated with TDP-43 levels and also differed between A382T and G348C. Together, TDP-43 and these factors may enable detection of abnormalities in individual ALS pathologies.