title: Differential distribution and energy status-dependent regulation of the four CART neuropeptide genes in the zebrafish brain.
abstract: The cocaine- and amphetamine-regulated transcript (CART) neuropeptide has been implicated in the neural regulation of energy homeostasis across vertebrate phyla. By using gene-specific in situ hybridization, we have mapped the distribution of the four CART mRNAs in the central nervous system of the adult zebrafish. The widespread neuronal expression pattern for CART 2 and 4 suggests a prominent role for the peptide in processing sensory information from diverse modalities including olfactory and visual inputs. In contrast, CART 1 and 3 have a much more restricted distribution, predominantly located in the nucleus of the medial longitudinal fasciculus (NMLF) and entopeduncular nucleus (EN), respectively. Enrichment of CART 2 and 4 in the preoptic and tuberal areas emphasizes the importance of CART in neuroendocrine functions. Starvation resulted in a significant decrease in CART-positive cells in the nucleus recessus lateralis (NRL) and nucleus lateralis tuberis (NLT) hypothalamic regions, suggesting a function in energy homeostasis for these neurons. Similarly, the EN emerges as a novel energy status-responsive region. Not only is there abundant and overlapping expression of CART 2, 3, and 4 in the EN, but also starvation induced a decrease in CART-expressing neurons in this region. The cellular resolution mapping of CART mRNA and the response of CART-expressing nuclei to starvation underscores the importance of CART neuropeptide in energy processing. Additionally, the regional and gene-specific responses to energy levels suggest a complex, interactive network whereby the four CART gene products may have nonredundant functions in energy homeostasis.
authors.affiliation: Indian Institute of Science Education and Research (IISER) Pune, Pune, 411 008, India.
authors.forename: G
authors.initials: G
authors.lastname: Akash
authors.forename: Tarun
authors.initials: T
authors.lastname: Kaniganti
authors.forename: Neeraj Kumar
authors.initials: NK
authors.lastname: Tiwari
authors.forename: Nishikant K
authors.initials: NK
authors.lastname: Subhedar
authors.forename: Aurnab
authors.initials: A
authors.lastname: Ghose
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D017403:In Situ Hybridization; D008297:Male; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D016415:Sequence Alignment; D013217:Starvation / Q000378:metabolism; D015027:Zebrafish / Q000235:genetics / Q000378:metabolism*; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism*; D000098882:Cocaine- and Amphetamine-Regulated Transcript Protein
chemical_list: D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D029961:Zebrafish Proteins; D000098882:Cocaine- and Amphetamine-Regulated Transcript Protein
keywords: CART neuropeptide; anorexic agent; energy homeostasis; in situ hybridization; zebrafish