Biology subjects

Parrington, B.

Publications and source records attributed to Parrington, B..

2 recordsLinked to original sources

bioRxiv2024

Circadian rhythms mediate malaria transmission potential

Malaria transmission begins when infected female Anopheles mosquitos deposit Plasmodium parasites into the mammalian hosts skin during a bloodmeal. The salivary gland-resident sporozoite parasites migrate to the bloodstream, subsequently invading and replicating within hepatocytes. As Anopheles mosquitos are more active at night, with a 24-hour rhythm, we investigated whether their salivary glands are under circadian control, anticipating bloodmeals and modulating sporozoite biology for host encounters. Here we show that approximately half of the mosquito salivary gland transcriptome, particularly genes essential for efficient bloodmeals such as anti-blood clotting factors, exhibits circadian rhythmic expression. Furthermore, we demonstrate that mosquitoes prefer to feed during nighttime, with the amount of blood ingested varying cyclically throughout the day. Notably, we show a substantial subset of the sporozoite transcriptome cycling throughout the day. These include genes involved in parasite motility, potentially modulating the ability to initiate infection at different times of day. Thus, although sporozoites are typically considered quiescent, our results demonstrate their transcriptional activity, revealing robust daily rhythms of gene expression. Our findings suggest a circadian evolutionary relationship between the vector, parasite and mammalian host that together modulate malaria transmission.

microbiology↗

bioRxiv2020

A Global Temporal Genetic Program for Neural Circuit Formation

The assembly of neural circuits is dependent upon precise spatiotemporal expression of cell recognition molecules1-6. Factors controlling cell-type specificity have been identified7-9, but how timing is determined remains unknown. Here we describe the induction of a cascade of transcription factors by a steroid hormone (Ecdysone) in all fly visual system neurons spanning target recognition and synaptogenesis. We demonstrate through single cell sequencing that the Ecdysone pathway regulates the expression of a common set of targets required for synaptic maturation and cell-type specific targets enriched for cell surface proteins regulating wiring specificity. Transcription factors in the cascade regulate the expression of the same wiring genes in complex ways, including activation in one cell-type and repression in another. We show that disruption of the Ecdysone-pathway generates specific defects in dendritic and axonal processes and synaptic connectivity, with the order of transcription factor expression correlating with sequential steps in wiring. We also identify shared targets of a cell-type specific transcription factor and the Ecdysone pathway which regulate specificity. We propose neurons integrate a global temporal transcriptional module with cell-type specific transcription factors to generate different cell-type specific patterns of cell recognition molecules regulating wiring.

neuroscience↗