Biology subjects

Carroll, P.

Publications and source records attributed to Carroll, P..

3 recordsLinked to original sources

bioRxiv2018

A GABAergic Maf-expressing interneuron subset regulates the speed of locomotion in Drosophila

Interneurons (INs) coordinate motoneurons activity to generate adequate patterns of muscle contractions, providing animals with the ability to adjust their body posture and to move over a range of speeds. In the Drosophila larvae several IN subtypes have been morphologically described and their function well documented. However, the general lack of molecular characterization of those INs prevents the identification of evolutionary counterparts in other model animals, limiting our understanding of widespread principles ruling neuronal circuits organization and functioning. Here we characterize a highly restricted neuronal subset expressing the Maf transcription factor Traffic Jam (TJ). We found that TJ+ neurons are highly diverse and their activation using intersectional genetics disrupted larval body posture and locomotion speed. We also showed that a small subset of TJ+ GABAergic INs, singled out by the unique expression of Per, Fkh, Grain and Hlh3b, a molecular signature reminiscent to V2b INs in vertebrate, impacted the larvae crawling speed.

neuroscience↗

bioRxiv2018

Optimization of the DsRed fluorescent protein for use in Mycobacterium tuberculosis

ABSTRACTO_ST_ABSObjectiveC_ST_ABSWe have previously codon-optimized a number of red fluorescent proteins for use in Mycobacterium tuberculosis (mCherry, tdTomato, Turbo-635). We aimed to expand this repertoire to include DsRed, another widely used and flexible red fluorescent protein.\n\nResultsWe generated expression constructs with a full length DsRed under the control of one of three strong, constitutive promoters (Phsp60, PrpsA or PG13) for use in mycobacteria. We confirmed that full length DsRed (225 amino acids) was expressed and fluoresced brightly. In contrast to mCherry, truncated versions of DsRed lacking several amino acids at the N-terminus were not functional. Thus, we have expanded the repertoire of optimized fluorescent proteins for mycobacteria.

molecular biology↗

bioRxiv2017

The MYC antagonist MNT autoregulates its expression and supports proliferation in MAX deficient cells

MNT is a transcription factor of the MXD family. MNT-MAX dimers down-regulate genes by binding to E-box sequences, which can also be bound by MYC-MAX to activate transcription. MNT has been described as a modulator of MYC activity but little is known about MNT regulation and whether MNT has MAX-independent functions. Using a MAX deficient cell line and siRNA-mediated silencing of MAX, we show that in the absence of MAX, the total MNT levels are elevated and that MNT localizes both in the cytoplasm and the nucleus. In contrast, MNT is predominantly nuclear when MAX is expressed. MNT is required for optimal cell proliferation even in the absence of MAX, being the first report of a MAX-independent function of MNT. Interestingly, MNT forms homodimers and autoregulates its expression by repressing its own promoter. The tight MNT regulation and its activity in absence of MAX suggest its importance on cell homeostasis.

cancer biology↗