Olfaction and innate behaviors
Significance: In this study we comprehensively characterized social stimuli emitted by pups and uncovered a multi-sensory logic of pup-recognition. We identified specific chemical and physical cues that trigger pup-directed aggression by virgin males and show that reconstituted, inanimate pup dummies can trigger pup-directed aggression.
Isogai, Y. (2013) Olfactory lexicon that controls innate behaviors, Kagaku-to-Seibutsu (Chemistry and Biology), 51(9), in Japanese.
Isogai, Y., Si, S., Tan, T., Pont-Lezica, L., Kapoor, V., Murthy, V., and Dulac, C. (2011) Molecular organization of vomeronasal chemoreception, Nature 478: 241-5.
Significance: This study provides a long elusive answer to the functions of vomeronasal receptors in pheromone detection. The logic of receptor usage for the detection of a variety of ecological and behaviorally significant cues provides a powerful experimental framework for our future research: to delineate neural circuits controlled by specific vomeronasal inputs linked to social and defensive behaviors such as mating, aggression, fear, parental behaviors, and social hierarchy.
Whole brain imaging using light sheet microscopy
Isogai, Y., Richardson, D., Dulac, C., and Bergan, J.F. (2017) Optimized protocol for imaging cleared neural issues using light microscopy, in Synapse Development, Methods in Molecular Biology, Springer, 1538: 137-153.
Menegas, W., Bergan, J.F., Ogawa, S.K., Isogai, Y., Venkataraju, K.U., Osten, P., Uchida, N., and Watabe-Uchida, M. (2015) Projection-specific inputome for dopamine neurons: dopamine neurons projecting to the posterior striatum form a distinct subclass, eLife, 4: e10032.
Significance: Above two studies provide significant technological advances on the imaging of whole mouse brains by a combination of CLARITY technique and light sheet microscopy.
King, N., Westbrook, J., Young, S., Abedin, M., Chapman, J., Fairclough, S., Hellsten, U., Isogai, Y. et al. (2008) The genome of the choanoflagellate Monosiga brevicollis and the origins of metazoan multicellularity, Nature 451:783-8.
Isogai, Y., Keles, S., Prestel, M., Hochheimer, A., and Tjian, R. (2007) Transcription of histone gene cluster by differential core-promoter factors, Genes & Development 21:2936-49.
Significance: In this study using ChIP-on-Chip, we identified >1,000 genes bound by TBP-related factor 2 (TRF2), a paralog of the TATA-box binding protein (TBP). This analysis revealed that TRF2 preferentially regulates TATA-less promoters and is excluded from TATA-box containing promoters. This study thus uncovered the molecular logic of core-promoter selectivity regulated by differential core-promoter factor usage.
Marr, M.T., Isogai, Y., Wright, K.J., and Tjian, R. (2006) Coactivator crosstalk specifies transcriptional output, Genes & Development 20:1458-69.
Significance: This study describes a novel imaging method to dissect the preinitiation complex assembly on promoter DNA in single cells. This study revealed a distinct order of preinitiation complex assembly in an inducible promoter. This is a pioneering study for the use of single cells to study biochemical mechanisms of transcriptional regulation.