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Kazunari Miyamichi

@k-miyamichi.bsky.social

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Team leader, RIKEN BDR, Kobe, Japan https://cco.riken.jp/index_en.html; Neuroscientist studying hypothalamus and sympathetic nervous systems in mice https://scholar.google.com/citations?user=yQZ8MFgAAAAJ; Any opinions expressed herein are personal.

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Kazunari Miyamichi @k-miyamichi.bsky.social · Dec 10

The sympathetic nervous system may control selective organs, but how this specificity is achieved is unknown. Our new study
@NatureComms www.nature.com/articles/s41...　uncovers a parallel labeled-line organization within the lower thoracic spinal cord. 1/

Parallel labeled-line organization of sympathetic outflow for selective organ regulation in mice - Nature Communications

How individual organs are specifically regulated by the sympathetic neurons at the cellular level remains not fully understood. Here, authors identify two molecularly distinct sympathetic pathways tha...

www.nature.com

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Kazunari Miyamichi @k-miyamichi.bsky.social · Jul 2

Happy to share our new work in Sci Adv! www.science.org/doi/10.1126/...　We found a robust representation of pup retrieval in the orbitofrontal cortex of female mice, which positively regulates VTA dopamine neurons during the acquisition of maternal behavior. Congrats to Gen-ichi and the team!

Orbitofrontal cortex influences dopamine dynamics associated with alloparental behavioral acquisition in female mice

Orbitofrontal cortex neurons facilitate alloparental behaviors in virgin female mice by modulating the dopamine system.

www.science.org

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Kazunari Miyamichi @k-miyamichi.bsky.social · May 12

The new paper is out in @PLOSONE: journals.plos.org/plosone/arti.... We introduce a novel knock-in mouse line for rabies-based trans-synaptic tracing, with a detailed discussion of its strengths and limitations.

A transgenic mouse line for rabies virus-mediated trans-synaptic tracing in the postnatal developing brain

Neural circuits are composed of numerous neurons that perform diverse functions. Understanding the mechanisms of neural processing requires elucidating the connections among individual neurons. Rabies...

journals.plos.org

Kazunari Miyamichi @k-miyamichi.bsky.social · Feb 24

Opus, sorry—I forgot to include the link to the paper! Here it is: www.cell.com/neuron/abstr...

Dietary availability acutely influences puberty onset via a hypothalamic neural circuit

Goto et al. measure the pulsatile activity of the reproductive center in the hypothalamic arcuate nucleus during puberty in female mice. They discover that food availability rapidly and bidirectionall...

www.cell.com

Kazunari Miyamichi @k-miyamichi.bsky.social · Feb 24

Side note: The first author Teppei Goto has been a dedicated neuroendocrinologist specializing in kisspeptin. His previous work (elifesciences.org/articles/82533) explored menopause, this study tackles puberty—could the next installment complete a life-course trilogy on reproductive transitions?

Dynamics of pulsatile activities of arcuate kisspeptin neurons in aging female mice

The pulsatile activities of kisspeptin neurons, the central pacemaker activities of reproductive functions, show unexpected robustness in terms of frequency, but a tendency for the intensity to declin...

elifesciences.org

Kazunari Miyamichi @k-miyamichi.bsky.social · Feb 24

PR from RIKEN www.riken.jp/press/2025/2... (Japanese only) ->
I would like to express my sincere thanks to Drs. Ken Murata (Univ. of Tokyo), Tomomi Karigo (Johns Hopkins), and Hiroko Sokumura (Nagoya Univ.) for their kind comments on the manuscript of this paper. (10/N

www.riken.jp

Kazunari Miyamichi @k-miyamichi.bsky.social · Feb 24

This study reveals a rapid regulatory mechanism in which AgRP neurons dynamically adjust reproductive timing in response to fluctuating food availability. How this "food-to-reproduction" circuit operates beyond the context of puberty remains an open question. (9/N

Kazunari Miyamichi @k-miyamichi.bsky.social · Feb 24

Conversely, partial ablation of AgRP neurons significantly increased kisspeptin pulsatility even under caloric restriction, allowing partial ovarian maturation. These findings establish AgRP neurons as key inhibitors of kisspeptin pulses, acting as a brake on puberty onset. (8/N

Kazunari Miyamichi @k-miyamichi.bsky.social · Feb 24

While all mice experienced their first estrus by P45 in the control group, only half reached puberty, and ovarian development was delayed, in the AgRP-activated group (C, D). (7/N

Kazunari Miyamichi @k-miyamichi.bsky.social · Feb 24

We then turned to AgRP neurons, key hunger sensors in the arcuate nucleus. AgRP neurons are known to be activated by fasting and rapidly suppressed by food availability. We found that artificially activating AgRP neurons blocked the surge in kisspeptin pulses even after refeeding (A, B). (6/N

Kazunari Miyamichi @k-miyamichi.bsky.social · Feb 24

Food scarcity is known to delay puberty, but how kisspeptin neurons sense metabolic status remains unclear. We found that under a mild caloric restriction suppressing puberty, low-frequency kisspeptin pulses persist. Once food availability was restored, pulsatile activity surged within hours. (5/N

Kazunari Miyamichi @k-miyamichi.bsky.social · Feb 24

Between P24 and P30, sharp peaks of pulsatile activity in kisspeptin neurons appeared. This activity preceded vaginal opening—the first visible sign of puberty—and increased in frequency with age. This provides definitive evidence that kisspeptin neuron pulses emerge before puberty onset. (4/N

Kazunari Miyamichi @k-miyamichi.bsky.social · Feb 24

Yet, due to technical challenges, the pulsatile activity of kisspeptin neurons in prepubertal animals remained uncharted. Using a genetic approach to express a Ca2+ sensor specifically in kisspeptin neurons, we successfully tracked their activity starting from P24 in mice. (3/N

Kazunari Miyamichi @k-miyamichi.bsky.social · Feb 24

An increase in the gonadotropin secretion rate drives sexual maturation. The master regulator of this rhythm is kisspeptin neurons in the hypothalamic arcuate nucleus. After maturity, these neurons fire in synchronized pulses every 30 min to 2 hrs, setting the pace for gonadotropin release. (2/N

Kazunari Miyamichi @k-miyamichi.bsky.social · Feb 24

If you are interested in what happens deep in the brain during puberty, please check our new paper in Neuron. We visualize how nutritional status shapes sexual maturation in female mice: A flagship study by an excellent postdoc Teppei Goto. (1/N

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Reposted by Kazunari Miyamichi

Neuron @cp-neuron.bsky.social · Feb 24

Dietary availability acutely influences puberty onset via a hypothalamic neural circuit

dlvr.it

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Kazunari Miyamichi @k-miyamichi.bsky.social · Feb 5

If you are interested in organ sensation and organ neural control, this is the place to be! The 11th NSN in Kobe symposium will be held on February 21 at the Kobe University School of Medicine campus (and zoom). It is free but registration is required. Please come and join us!

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Kazunari Miyamichi @k-miyamichi.bsky.social · Jan 22

If you are interested in the neuroscience of lactation, here is my new review paper('ω')ノ www.sciencedirect.com/science/arti...

Oxytocin and neuroscience of lactation: Insights from the molecular genetic approach

In mammals, lactation is essential for the health and growth of infants and supports the formation of the mother–infant bond. Breastfeeding is mediate…

www.sciencedirect.com

Kazunari Miyamichi @k-miyamichi.bsky.social · Jan 16

Congratulations to Drs. Neyama and Cui on this fantastic publication!

Kazunari Miyamichi @k-miyamichi.bsky.social · Jan 16

The placebo treatment, working simply because it is perceived as a drug, has even been observed in rats. Dr. Cui’s research investigates the neural mechanisms underlying the placebo analgesic effect, to which I contributed by supporting the RV tracing system.
www.science.org/doi/10.1126/...

Opioidergic activation of the descending pain inhibitory system underlies placebo analgesia

The placebo effect can relieve pain by activating the brain’s pain inhibition system via endogenous opioidergic signals.

www.science.org

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Kazunari Miyamichi @k-miyamichi.bsky.social · Dec 25

Big congrats!

Reposted by Kazunari Miyamichi

Fumiaki Obata @obataf-lab.bsky.social · Dec 24

new work out from the lab @cellreports.bsky.social
A brave phd student Ayano revealed the mechanism how immune activation disrupts renal tubules! The key is a nonsecretory antimicrobial peptide!
www.cell.com/cell-reports...

A nonsecretory antimicrobial peptide mediates inflammatory organ damage in Drosophila renal tubules

Using the power of Drosophila genetics, Oi et al. identified a nonsecretory antimicrobial peptide, Attacin-D, as an essential factor in inflammatory organ damage in the renal tubules. This study highlights a key player in inflammatory organ injury.

www.cell.com

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Reposted by Kazunari Miyamichi

Kota Mizumoto @kota-mizumoto.bsky.social · Dec 23

Published! We've made a collection of knock-in strains to label endogenous active zone proteins. 'A modular system to label endogenous presynaptic proteins using split fluorophores in C. elegans' academic.oup.com/genetics/adv...

A modular system to label endogenous presynaptic proteins using split fluorophores in C. elegans

Abstract. Visualizing the subcellular localization of presynaptic proteins with fluorescent proteins is a powerful tool to dissect the genetic and molecula

academic.oup.com

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Kazunari Miyamichi @k-miyamichi.bsky.social · Dec 21

Thanks for the many citations this year🥰 The TRAP paper is experiencing a breakthrough over ten years after its publication!
Since transcriptome types and active neurons don’t always correlate in many cases, I anticipate that methods like this will continue to be useful😄

Reposted by Kazunari Miyamichi

neuroradio.bsky.social @neuroradio.bsky.social · Dec 21

#83 Emo
コンディショニングの変化、Bluesky移行など。論文紹介は、valenceに応じた伝達物質放出の変化、生きた細胞からのトランスクリプトミクス、空腹による恐怖表象の変化。
#NeuroRadio #神経科学 #ポッドキャスト
neuroradio.tokyo/2024/12/21/8...

#83 Emo - NeuroRadio

ハーフマラソン参加を通じたコンディショニングの変化、Bluesky移行など。論文紹介は、valenceに応じた伝達物質放出の変化、生きた細胞からのトランスクリプトミクス、空腹による恐怖表象の変化 (12/15収録) Sh...

neuroradio.tokyo

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Kazunari Miyamichi @k-miyamichi.bsky.social · Dec 13

This research opens a new avenue of real-time, single-cell-level neuroendocrinology in freely behaving animals. We extend our heartfelt thanks to Drs. Tomomi Karigo and Takuya Osakada for their thoughtful comments on the manuscript! 7/