Bart Lodder

Neuroscience graduate student in the Sabatini Lab @harvard

[Bernardo Sabatini @blsabatini]

Neuron classes are distinguished by expression of many genes, including those for ion channel subunits. In cortex, PV+ neurons are the major expressors of Kcng4, which encodes for the K-channel "silent" subunit Kv6.4. @SanikaGanesh led this work showing that Kv6.4 regulates

[Bernardo Sabatini @blsabatini]

Not sure who is still out there but we're proud of this work led by @lodder_bart that (1) propose a new method to turn intensity sensors into lifetime sensors and (2) applies it to GCAMP8m to make an excellent lifetime Ca sensor.
https://t.co/K5GRDLfNYe

[Bart Lodder @lodder_bart]

5. We show, in behaving mice, that baseline calcium is correlated with the firing rate of individual neurons and that baseline calcium dynamically changes in response to visual stimulation and changes in firing rate

[Bart Lodder @lodder_bart]

We posted a new paper on biorxiv describing LifeCamp, a new high speed calcium lifetime sensor. LifeCamp enables detection of baseline calcium, neuronal firing and artifact insensitive comparisons across experiments, brain regions and long timescales.

https://t.co/YwXA2kSiPQ

[Bart Lodder @lodder_bart]

4. We show that LifeCamp allows for more accurate measurement of population activity, using fluorescence lifetime photometry at high temporal resolution (FLIPR). LifeCamp is insensitive to intensity artifacts and allows for the capture of long term changes in calcium levels.

[Tarun Kamath @TVKamath]

Excited to share some of my PhD work out today in @NeuroCellPress! We use our novel lifetime photometry system with the new dLight3.8 sensor to study hunger induced changes in exploration and risk assessment derive from AgRP modulation of dopamine signaling in tail of striatum.

[Bernardo Sabatini @blsabatini]

Our latest led by @TVKamath with important contributions by collaborators including Nao Uchida, Mitsuko Watabe-Uchida and @LinTianPhD
Hunger modulates exploration through suppression of dopamine signaling in the tail of the striatum: Neuron https://t.co/AY83gxziHJ

[Bart Lodder @lodder_bart]

6/ Altogether, FLIPR allows for easy and robust absolute measurement of fast and slow neurotransmitter release and together with new lifetime sensors such as dLight3.8 will give neuroscientist new capabilities to measure neuronal signals for fundamental and disease research

[Bart Lodder @lodder_bart]

Our fluorescence lifetime photometry at high temporal resolution (FLIPR) paper is now online at Neuron. FLIPR allows for fast (10Hz-1 kHz) and slow (min-hrs) measurement of absolute neuronal signals in freely moving mice. We highlight the utility by measuring tonic and phasic DA.

[Neuron @NeuroCellPress]

Online now: Absolute measurement of fast and slow neuronal signals with fluorescence lifetime photometry at high temporal resolution https://t.co/hl5xaGMiag

[Bart Lodder @lodder_bart]

5/ Finally, we developed a two-color FLIPR system, which allowed us to simultaneously record absolute dopamine and calcium in D1 receptor neurons in freely moving mice.

[Bart Lodder @lodder_bart]

@tpatriarchi Thank you for the suggestion! This chemogenetic tool is very useful and can be used simultaneously with FLIPR to boost the tonic signal. In order to claim absolute measurement one would have to of course very carefully characterize the stable regime of DETQ affinity modulation

[Bart Lodder @lodder_bart]

If you are interested how to measure absolute neurotransmitter release or neuronal signals in vivo over long time-scales and at high speed, please check out our new pre-print, where we use FLIPR to measure phasic and tonic dopamine in freely moving mice. https://t.co/MMw2B6y6Ok

[Bart Lodder @lodder_bart]

@yaochen20 Thank you Yao!

[Bart Lodder @lodder_bart]

5/ In this preprint, we show that FLIPR is a powerful technology that will allow the community access to absolute fast and slow signal measurement in vivo. Thank you to my mentors @blsabatini Roger Adan, coauthors and Sabatini lab members