Biology subjects

Bento, F.

Publications and source records attributed to Bento, F..

2 recordsLinked to original sources

bioRxiv2020

A long non-coding RNA controls parasite differentiation in African trypanosomes

Trypanosoma brucei causes African sleeping sickness, a fatal human disease. Its differentiation from replicative slender form into quiescent stumpy form promotes host survival and parasite transmission. Long noncoding RNAs (lncRNAs) are known to regulate cell differentiation. To determine whether lncRNAs are involved in parasite differentiation we used RNAseq to survey the T. brucei lncRNA gene repertoire, identifying 1,428 previously uncharacterized lncRNA genes. We analysed grumpy, a lncRNA located immediately upstream of an RNA-binding protein that is a key differentiation regulator. Grumpy over-expression resulted in premature parasite differentiation into the quiescent stumpy form, and subsequent impairment of in vivo infection, decreasing parasite load in the mammalian host, and increasing host survival. Our analyses suggest Grumpy is one of many lncRNA that modulate parasite-host interactions, and lncRNA roles in cell differentiation are probably commonplace in T. brucei.

microbiology↗

bioRxiv2019

RNase H1 and H2 are differentially regulated to eliminate RNA-DNA hybrids

RNA-DNA hybrids are tightly regulated to ensure genome integrity. The RNase H enzymes, RNase H1 and H2, contribute to chromosomal stability through the removal of RNA-DNA hybrids. Loss of RNase H2 function is implicated in human diseases of the nervous system and cancer. To better understand RNA-DNA hybrid dynamics, we have focused on elucidating the regulation of the RNase H enzymes themselves. Using yeast as a model system, we demonstrate that RNase H1 and H2 are controlled in different manners. RNase H2 is regulated in a strict cell cycle dependent manner, both in terms of its R-loop removal, and ribonucleotide excision repair functions. RNase H1, however, can function independent of cell cycle stage to remove R-loops, but appears to become activated in response to high R-loop loads. These results provide us with a more complete understanding of how and when RNA-DNA hybrids are acted upon by the RNase H enzymes.

molecular biology↗