Luna, L. | Search bioRxiv

bioRxiv2021

NEIL1 and NEIL2 DNA glycosylases regulate anxiety and learning in a cooperative manner

Oxidative DNA damage in the brain has been implicated in neurodegeneration and cognitive decline. DNA glycosylases initiate base excision repair (BER), the main pathway for oxidative DNA base lesion repair. NEIL1 and NEIL3 DNA glycosylases alter cognition in mice, the role of NEIL2 remains unclear. Here, we investigate the impact of NEIL2 and its potential overlap with NEIL1 on behavior in single and double knock-out mouse models. Neil1-/-Neil2-/- mice displayed hyperactivity, reduced anxiety and improved learning. Hippocampal oxidative DNA base lesion levels were comparable between genotypes, no mutator phenotype was found. Impaired canonical repair was thus not the cause of altered behavior. Electrophysiology indicated reduced stratum oriens afferents in the hippocampal CA1 region in Neil1-/-Neil2-/-. Within CA1, NEIL1 and NEIL2 jointly regulated transcription in genes relevant for synaptic function. Thus, we postulate a cooperative function of NEIL1 and NEIL2 in genome regulation beyond canonical BER modulating memory formation and anxiety.

molecular biology↗

bioRxiv2020

Genomic diversity, population structure and accessory genome analysis of Pasteurella multocida: New Insights into host adaptation and disease specialization

Pasteurella multocida is a multi-host pathogen that infects a wide spectrum of domestic and wild animals including humans. Despite its impact on health and economics, P. multocida is considered an enigmatic pathogen and the genetic basis of its pathogenicity and host adaptation still remains unclear. Here we present a detailed genomic framework based on 336 whole-genome sequences of P. multocida isolates from different animal species and countries. Our data provide genomic support of the existence of two very divergent phylogroups (PmI and PmII), which present a barrier to homologous recombination suggesting genetic isolation. Additionally, a torCAD operon, which reduces TMAO (trimethylamine N-oxide) to produce energy during bacterial anaerobic respiration, is present only in PmI and can act as a hypothetical driver of niche segregation between phylogroups. The PmI phylogroup harbors strains that infect a wider range of hosts than PmII, and shows a highly diverse phylogeny and accessory genome. We identified nine clonal lineages for PmI, seven of which are associated with specific hosts or diseases and contain distinct accessory gene pools that can confer ecologically relevant phenotypes. We found differential presence of a trehalose metabolism operon in the bovine lineage associated with pneumonic pasteurellosis; while, citrate, L-arabinose, L-fucose, and D-allose operons are only present in avian lineages. These findings suggest that alternative metabolic pathways may facilitate the establishment of P. multocida during host colonization in the early stages of infection promoting the adaptation of P. multocida lineages to certain hosts.

microbiology↗