title: AP1 transcription factors are required to maintain the peripheral taste system.
abstract: The sense of taste is used by organisms to achieve the optimal nutritional requirement and avoid potentially toxic compounds. In the oral cavity, taste receptor cells are grouped together in taste buds that are present in specialized taste papillae in the tongue. Taste receptor cells are the cells that detect chemicals in potential food items and transmit that information to gustatory nerves that convey the taste information to the brain. As taste cells are in contact with the external environment, they can be damaged and are routinely replaced throughout an organism's lifetime to maintain functionality. However, this taste cell turnover loses efficiency over time resulting in a reduction in taste ability. Currently, very little is known about the mechanisms that regulate the renewal and maintenance of taste cells. We therefore performed RNA-sequencing analysis on isolated taste cells from 2 and 6-month-old mice to determine how alterations in the taste cell-transcriptome regulate taste cell maintenance and function in adults. We found that the activator protein-1 (AP1) transcription factors (c-Fos, Fosb and c-Jun) and genes associated with this pathway were significantly downregulated in taste cells by 6 months and further declined at 12 months. We generated conditional c-Fos-knockout mice to target K14-expressing cells, including differentiating taste cells. c-Fos deletion caused a severe perturbation in taste bud structure and resulted in a significant reduction in the taste bud size. c-Fos deletion also affected taste cell turnover as evident by a decrease in proliferative marker, and upregulation of the apoptotic marker cleaved-PARP. Thus, AP1 factors are important regulators of adult taste cell renewal and their downregulation negatively impacts taste maintenance.
authors: Department of Biological Sciences, University at Buffalo, Buffalo, NY 14260, USA.
authors: Jayasha
authors: J
authors: Shandilya
authors: Department of Biological Sciences, University at Buffalo, Buffalo, NY 14260, USA.
authors: Yankun
authors: Y
authors: Gao
authors: Department of Physiology & Biophysics, University at Buffalo, Buffalo, NY 14214, USA.
authors: Tapan K
authors: TK
authors: Nayak
authors: Department of Biological Sciences, University at Buffalo, Buffalo, NY 14260, USA.
authors: Stefan G E
authors: SG
authors: Roberts
authors: Department of Biological Sciences, University at Buffalo, Buffalo, NY 14260, USA.
authors: Kathryn F
authors: KF
authors: Medler
mesh_terms: D051697:Activating Transcription Factor 1 / Q000378:metabolism*; D000375:Aging / Q000378:metabolism; D000818:Animals; D017209:Apoptosis / Q000235:genetics; D002454:Cell Differentiation / Q000235:genetics; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D018345:Mice, Knockout; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017423:Sequence Analysis, RNA; D013649:Taste; D013650:Taste Buds / Q000378:metabolism
chemical_list: D051697:Activating Transcription Factor 1; D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger