@article {67673, title = {Spatially patterned excitatory neuron subtypes and projections of the claustrum.}, journal = {eLife}, volume = {10}, year = {2021}, month = {2021 Aug 16}, abstract = {

The claustrum is a functionally and structurally complex brain region, whose very spatial extent remains debated. Histochemical-based approaches typically treat the claustrum as a relatively narrow anatomical region that primarily projects to the neocortex, whereas circuit-based approaches can suggest a broader claustrum region containing projections to the neocortex and other regions. Here, in the mouse, we took a bottom-up and cell-type-specific approach to complement and possibly unite these seemingly disparate conclusions. Using single-cell RNA-sequencing, we found that the claustrum comprises two excitatory neuron subtypes that are differentiable from the surrounding cortex. Multicolor retrograde tracing in conjunction with 12-channel multiplexed in situ hybridization revealed a core-shell spatial arrangement of these subtypes, as well as differential downstream targets. Thus, the claustrum comprises excitatory neuron subtypes with distinct molecular and projection properties, whose spatial patterns reflect the narrower and broader claustral extents debated in previous research. This subtype-specific heterogeneity likely shapes the functional complexity of the claustrum.

}, issn = {2050-084X}, doi = {10.7554/eLife.68967}, author = {Erwin, Sarah R and Bristow, Brianna N and Sullivan, Kaitlin E and Kendrick, Rennie M and Marriott, Brian and Wang, Lihua and Clements, Jody and Lemire, Andrew L and Jackson, Jesse and Cembrowski, Mark S} } @article {65313, title = {The anatomy and physiology of claustrum-cortex interactions.}, journal = {Annual Review of Neuroscience}, volume = {43}, year = {2020}, month = {2020 Jul 1}, pages = {231-47}, abstract = {

The claustrum is one of the most widely connected regions of the forebrain, yet its function has remained obscure, largely due to the experimentally challenging nature of targeting this small, thin, and elongated brain area. However, recent advances in molecular techniques have enabled the anatomy and physiology of the claustrum to be studied with the spatiotemporal and cell type-specific precision required to eventually converge on what this area does. Here we review early anatomical and electrophysiological results from cats and primates, as well as recent work in the rodent, identifying the connectivity, cell types, and physiological circuit mechanisms underlying the communication between the claustrum and the cortex. The emerging picture is one in which the rodent claustrum is closely tied to frontal/limbic regions and plays a role in processes, such as attention, that are associated with these areas. Expected final online publication date for the , Volume 43 is July 8, 2020. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

}, issn = {1545-4126}, doi = {10.1146/annurev-neuro-092519-101637}, author = {Jackson, Jesse and Smith, Jared B and Lee, Albert K} } @article {65872, title = {The claustrum.}, journal = {Current Biology}, volume = {30}, year = {2020}, month = {2020 Dec 07}, pages = {R1401-R1406}, abstract = {

The claustrum is a brain region that has been investigated for over 200 years, yet its precise function remains unknown. In the final posthumously released article of Francis Crick, written with Christof Koch, the claustrum was suggested to be critically linked to consciousness. Though the claustrum remained relatively obscure throughout the last half century, it has enjoyed a renewed interest in the last 15 years since Crick and Koch{\textquoteright}s article. During this time, the claustrum, like many other brain regions, has been studied with the myriad of modern systems neuroscience tools that have been made available by the intersection of genetic and viral technologies. This has uncovered new information about its anatomical connectivity and physiological properties and begun to reveal aspects of its function. From these studies, one clear consensus has emerged which supports Crick and Koch{\textquoteright}s primary interest in the claustrum: the claustrum has widespread extensive connectivity with the entire cerebral cortex, suggesting a prominent role in {\textquoteright}higher order processes{\textquoteright}.

}, issn = {1879-0445}, doi = {10.1016/j.cub.2020.09.069}, author = {Smith, Jared B and Lee, Albert K and Jackson, Jesse} } @article {65067, title = {Neuron-astrocyte metabolic coupling protects against activity-induced fatty acid toxicity.}, journal = {Cell}, volume = {177}, year = {2019}, month = {2019 May 30}, pages = {1522-1535.e14}, abstract = {

Metabolic coordination between neurons and astrocytes is critical for the health of the brain. However, neuron-astrocyte coupling of lipid metabolism, particularly in response to neural activity, remains largely uncharacterized. Here, we demonstrate that toxic fatty acids (FAs) produced in hyperactive neurons are transferred to astrocytic lipid droplets by ApoE-positive lipid particles. Astrocytes consume the FAs stored in lipid droplets via mitochondrial β-oxidation in response to neuronal activity and turn on a detoxification gene expression program. Our findings reveal that FA metabolism is coupled in neurons and astrocytes to protect neurons from FA toxicity during periods of enhanced activity. This coordinated mechanism for metabolizing FAs could underlie both homeostasis and a variety of disease states of the brain.

}, issn = {1097-4172}, doi = {10.1016/j.cell.2019.04.001}, author = {Ioannou, Maria S and Jackson, Jesse and Sheu, Shu-Hsien and Chang, Chi-Lun and Weigel, Aubrey V and Liu, Hui and Pasolli, H Amalia and Xu, C Shan and Pang, Song and Matthies, Doreen and Hess, Harald F and Lippincott-Schwartz, Jennifer and Liu, Zhe} } @article {49369, title = {Inhibitory control of prefrontal cortex by the claustrum.}, journal = {Neuron}, volume = {99}, year = {2018}, month = {2018 Aug 07}, pages = {1029-39}, abstract = {

The claustrum is a small subcortical nucleus that has extensive excitatory connections with many cortical areas. While the anatomical connectivity from the claustrum to the cortex has been studied intensively, the physiological effect and underlying circuit mechanisms of claustrocortical communication remain elusive. Here we show that the claustrum provides strong, widespread, and long-lasting feedforward inhibition of the prefrontal cortex (PFC) sufficient to silence ongoing neural activity. This claustrocortical feedforward inhibition was predominantly mediated by interneurons containing neuropeptide Y, and to a lesser extent those containing parvalbumin. Therefore, in contrast to other long-range excitatory inputs to the PFC, the claustrocortical pathway is designed to provide overall inhibition of cortical activity. This unique circuit organization allows the claustrum to rapidly and powerfully suppress cortical networks and suggests a distinct role for the claustrum in regulating cognitive processes in prefrontal circuits.

}, issn = {1097-4199}, doi = {10.1016/j.neuron.2018.07.031}, author = {Jackson, Jesse and Karnani, Mahesh M and Zemelman, Boris V and Burdakov, Denis and Lee, Albert K} }