Biology subjects

Roach, M.

Publications and source records attributed to Roach, M..

3 recordsLinked to original sources

bioRxiv2026

Photostimulus intensity, rather than colour or polarization, is the key driver for stable fly visual attraction in laboratory bioassays

Foraging hematophagous flies such as the stable fly, Stomoxys calcitrans, are shown or expected to sense multiple characteristics of visual host cues. These include relative intensity, spectral composition, and the angle and degree of polarization. Here, we investigated the role of each of these visual cue characteristics on stable fly attraction. In laboratory two-choice bioassays, we offered groups of female or male stable flies a choice between paired photostimuli that differed in their visual characteristics, recording the flies' landing responses on stimuli as the response criterion. Bioassay flies preferentially selected lower-intensity visual stimuli even when paired stimuli markedly differed in spectral composition and polarization characteristics (a high degree of horizontal or vertical polarization). When paired stimuli had identical relative intensity, flies failed to discriminate between the stimulus that presented ultraviolet, blue, green, and red wavebands and a corresponding paired stimulus lacking one of these wavebands. Our results support the hypothesis that foraging stable flies may respond to colour and polarization characteristics of visual stimuli as modulations of perceived intensity. Acquired knowledge on the mechanisms that underlie stable fly visual attraction may inform the design of vision-based traps so that they become optimally attractive to stable flies and other biting flies.

animal behavior and cognition↗

bioRxiv2026

Vertical inhibition of the autophagy pathway impairs growth and enhances sensitivity to mTORC1 inhibition in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is dependent on autophagy for growth. Chloroquine/Hydroxychloroquine (CQ/HCQ), the sole FDA-approved autophagy inhibitors, have shown limited clinical efficacy as cancer therapies. To identify approaches to improve PDAC response to CQ, we performed a CQ-anchored, CRISPR-Cas9 mediated loss-of-function screen. We identified that the loss of genes encoding proteins upstream in the autophagy pathway enhanced CQ-mediated growth suppression. This indicated that simultaneous targeting of two distinct nodes of the same pathway, vertical inhibition, may be a more effective strategy than single node inhibition. We demonstrated that genetic loss or pharmacological inhibition of VPS34, a protein necessary for autophagosome nucleation, sensitized PDAC cells to inhibitors of the terminal stage of the autophagy pathway, including CQ and an inhibitor of PIKfyve. We extended this concept to the initiation complex and demonstrated that ULK1/2 inhibition synergized with CQ and PIKfyve inhibition to impair PDAC cell growth and increase apoptosis. Anticipating mechanisms of resistance to vertical autophagy inhibition, we performed reverse-phase protein array profiling and identified that vertical inhibition of the autophagy pathway resulted in enhanced activation of the PI3K-AKT-mTORC1 signaling pathway. Increased mTORC1 signaling resulted in heightened sensitivity to bi-steric mTORC1 inhibition in both cell line and organoid models of PDAC. This study identifies novel anti-autophagy inhibitor combinations that may improve the clinical efficacy of autophagy inhibition for PDAC treatment. IMPLICATIONSVertical inhibition of the autophagy pathway reduces pancreatic cancer cell growth, increases apoptosis, and enhances sensitivity to mTORC1 inhibition; thereby representing a novel therapeutic strategy for autophagy-driven pancreatic cancer.

Cancer Biology↗

bioRxiv2026

Targeted sequencing of mutations via RNA-templated gap filling of oligonucleotides for single-cell RNA-seq

We describe a method for targeted sequencing of expressed mutations in single cells. The approach exploits the reverse transcriptase and nick translation activities of the Bst DNA polymerase (Full Length) from Bacillus stearothermophilus (BstFL) to perform an RNA-templated gap filling and ligation between flanking probes. Integrated with probe-based single cell RNAseq workflows, it enables simultaneous whole transcriptomic and multiplexed mutation profiling from the same cell, overcoming key limitations of mutation detection in existing scRNA-seq approaches.

molecular biology↗