Decoding neuronal composition and ontogeny of individual hypothalamic nuclei

The hypothalamus plays crucial roles in regulating endocrine, autonomic, and behavioral functions via its diverse nuclei and neuronal subtypes. The developmental mechanisms underlying ontogenetic establishment of different hypothalamic nuclei and generation of neuronal diversity remain largely unknown. Here, we show that combinatorial T-box 3 (TBX3), orthopedia homeobox (OTP), and distal-less homeobox (DLX) expression delineates all arcuate nucleus (Arc) neurons and defines four distinct subpopulations, whereas combinatorial NKX2.1/SF1 and OTP/DLX expression identifies ventromedial hypothalamus (VMH) and tuberal nucleus (TuN) neuronal subpopulations, respectively. Developmental analysis indicates that all four Arc subpopulations are mosaically and simultaneously generated from embryonic Arc progenitors, whereas glutamatergic VMH neurons and GABAergic TuN neurons are sequentially generated from common embryonic VMH progenitors. Moreover, clonal lineage-tracing analysis reveals that diverse lineages from multipotent radial glia progenitors orchestrate Arc and VMH-TuN establishment. Together, our study reveals cellular mechanisms underlying generation and organization of diverse neuronal subtypes and ontogenetic establishment of individual nuclei in the mammalian hypothalamus. [Display omitted] •Combinatorial TF expression identifies all Arc, VMH, and TuN neurons•All four subpopulations in the Arc are mosaically and simultaneously generated•Glutamatergic VMH and GABAergic TuN neurons are generated from common progenitors•Diverse lineages from individual radial glia progenitors build the Arc and VMH-TuN The cellular mechanisms underlying development and organization of hypothalamic nuclei are poorly understood. Using transcription factor expression combinations and clonal lineage-tracing analysis, Ma et al. reveal that diverse lineages from multipotent radial glia progenitors establish neuronal diversity and orchestrate ontogenetic development of hypothalamic arcuate nucleus, ventromedial hypothalamus, and tuberal nucleus.