Hypoglossal motor neurons(HMNs) innervate tongue muscles and play key roles in a variety of physiological functions,including swallowing,mastication,suckling,vocalization,and respiration.Dysfunction of HMNs is associa...Hypoglossal motor neurons(HMNs) innervate tongue muscles and play key roles in a variety of physiological functions,including swallowing,mastication,suckling,vocalization,and respiration.Dysfunction of HMNs is associated with several diseases,such as obstructive sleep apnea(OSA) and sudden infant death syndrome.OS A is a serious breathing disorder associated with the activity of HMNs during different sleep-wake states.Identifying the neural mechanisms by which the statedependent activities of HMNs are controlled may be helpful in providing a theoretical basis for effective therapy for OSA.However,the presynaptic partners governing the activity of HMNs remain to be elucidated.In the present study,we used a cell-type-specific retrograde tracing system based on a modified rabies virus along with a Cre/loxP gene-expression strategy to map the whole-brain monosynaptic inputs to HMNs in mice.We identified 53 nuclei targeting HMNs from six brain regions:the amygdala,hypothalamus,midbrain,pons,medulla,and cerebellum.We discovered that GAB Aergic neurons in the central amygdaloid nucleus,as well as calretinin neurons in the parasubthalamic nucleus,sent monosynaptic projections to HMNs.In addition,HMNs received direct inputs from several regions associated with respiration,such as the preBotzinger complex,parabrachial nucleus,nucleus of the solitary tract,and hypothalamus.Some regions engaged in sleep-wake regulation(the parafacial zone,parabrachial nucleus,ventral medulla,sublaterodorsal tegmental nucleus,dorsal raphe nucleus,periaqueductal gray,and hypothalamus) also provided primary inputs to HMNs.These results contribute to further elucidating the neural circuits underlying disorders caused by the dysfunction of HMNs.展开更多
Anterograde viral tracers are powerful and essential tools for dissecting the output targets of a brain region of interest. They have been developed from herpes simplex virus 1(HSV-1) strain H129(H129), and have been ...Anterograde viral tracers are powerful and essential tools for dissecting the output targets of a brain region of interest. They have been developed from herpes simplex virus 1(HSV-1) strain H129(H129), and have been successfully applied to map diverse neural circuits.Initially, the anterograde polysynaptic tracer H129-G4 was used by many groups. We then developed the first monosynaptic tracer, H129-dTK-tdT, which was highly successful, yet improvements are needed. Now, by inserting another tdTomato expression cassette into the H129-dTK-tdT genome, we have created H129-dTK-T2, an updated version of H129-dTK-tdT that has improved labeling intensity. To help scientists produce and apply our H129-derived viral tracers, here we provide the protocol describing our detailed and standardized procedures. Commonly-encountered technical problems and their solutions are also discussed in detail. Broadly, the dissemination of this protocol will greatly support scientists to apply these viral tracers on a large scale.展开更多
The lateral habenula(LHb),which is a critical neuroanatomical hub and a regulator of midbrain monoaminergic centers,is activated by events resulting in negative valence and contributes to the expression of both appeti...The lateral habenula(LHb),which is a critical neuroanatomical hub and a regulator of midbrain monoaminergic centers,is activated by events resulting in negative valence and contributes to the expression of both appetitive and aversive behaviors.However,whole-brain cell-type-specific monosynaptic inputs to the LHb in both sexes remain incompletely elucidated.In this study,we used viral tracing combined with in situ hybridization targeting vesicular glutamate transporter 2(vGlut2)and glutamic acid decarboxylase 2(Gad2)to generate a comprehensive whole-brain atlas of inputs to glutamatergic andγ-aminobutyric acid(GABA)ergic neurons in the LHb.We found>30 ipsilateral and contralateral brain regions that projected to the LHb.Of these,there were significantly more monosynaptic LHb-projecting neurons from the lateral septum,anterior hypothalamus,dorsomedial hypothalamus,and ventromedial hypothalamus in females than in males.More interestingly,we found a stronger GABAergic projection from the medial septum to the LHb in males than in females.Our results reveal a comprehensive connectivity atlas of glutamatergic and GABAergic inputs to the LHb in both sexes,which may facilitate a better understanding of sexual dimorphism in physiological and pathological brain functions.展开更多
基金supported by the National Natural Science Foundation of China (31530035,81420108015, 31671099,31871072,81570081,81770083 and 31971110)the National Basic Research Development Program of China (2015CB856401)+2 种基金the Program for Shanghai Outstanding Academic Leaders (to ZLH)the Shanghai Municipal Science and Technology Major Project (2018SHZDZX01)the National Key Research and Development Program of China (2018YFC1313600)。
文摘Hypoglossal motor neurons(HMNs) innervate tongue muscles and play key roles in a variety of physiological functions,including swallowing,mastication,suckling,vocalization,and respiration.Dysfunction of HMNs is associated with several diseases,such as obstructive sleep apnea(OSA) and sudden infant death syndrome.OS A is a serious breathing disorder associated with the activity of HMNs during different sleep-wake states.Identifying the neural mechanisms by which the statedependent activities of HMNs are controlled may be helpful in providing a theoretical basis for effective therapy for OSA.However,the presynaptic partners governing the activity of HMNs remain to be elucidated.In the present study,we used a cell-type-specific retrograde tracing system based on a modified rabies virus along with a Cre/loxP gene-expression strategy to map the whole-brain monosynaptic inputs to HMNs in mice.We identified 53 nuclei targeting HMNs from six brain regions:the amygdala,hypothalamus,midbrain,pons,medulla,and cerebellum.We discovered that GAB Aergic neurons in the central amygdaloid nucleus,as well as calretinin neurons in the parasubthalamic nucleus,sent monosynaptic projections to HMNs.In addition,HMNs received direct inputs from several regions associated with respiration,such as the preBotzinger complex,parabrachial nucleus,nucleus of the solitary tract,and hypothalamus.Some regions engaged in sleep-wake regulation(the parafacial zone,parabrachial nucleus,ventral medulla,sublaterodorsal tegmental nucleus,dorsal raphe nucleus,periaqueductal gray,and hypothalamus) also provided primary inputs to HMNs.These results contribute to further elucidating the neural circuits underlying disorders caused by the dysfunction of HMNs.
基金supported by the National Key Basic Research Program of China (2015CB755601)the National Natural Science Foundation of China (81427801, 81571355, and 81601206)the National Institutes of Health RF1 Funding of China (RF1MH120020-01)。
文摘Anterograde viral tracers are powerful and essential tools for dissecting the output targets of a brain region of interest. They have been developed from herpes simplex virus 1(HSV-1) strain H129(H129), and have been successfully applied to map diverse neural circuits.Initially, the anterograde polysynaptic tracer H129-G4 was used by many groups. We then developed the first monosynaptic tracer, H129-dTK-tdT, which was highly successful, yet improvements are needed. Now, by inserting another tdTomato expression cassette into the H129-dTK-tdT genome, we have created H129-dTK-T2, an updated version of H129-dTK-tdT that has improved labeling intensity. To help scientists produce and apply our H129-derived viral tracers, here we provide the protocol describing our detailed and standardized procedures. Commonly-encountered technical problems and their solutions are also discussed in detail. Broadly, the dissemination of this protocol will greatly support scientists to apply these viral tracers on a large scale.
基金This work was supported by the NSFC-Guangdong Joint Fund(U20A6005)the National Natural Science Foundation of China(31630031 and 31930047)+2 种基金the Key-Area Research and Development Program of Guangdong Province(2018B030340001 and 2018B030331001)the Guangdong Provincial Key Laboratory of Brain Connectome and Behavior(2017B030301017)the Shenzhen Key Laboratory of Translational Research for Brain Diseases(ZDSYS20200828154800001).
文摘The lateral habenula(LHb),which is a critical neuroanatomical hub and a regulator of midbrain monoaminergic centers,is activated by events resulting in negative valence and contributes to the expression of both appetitive and aversive behaviors.However,whole-brain cell-type-specific monosynaptic inputs to the LHb in both sexes remain incompletely elucidated.In this study,we used viral tracing combined with in situ hybridization targeting vesicular glutamate transporter 2(vGlut2)and glutamic acid decarboxylase 2(Gad2)to generate a comprehensive whole-brain atlas of inputs to glutamatergic andγ-aminobutyric acid(GABA)ergic neurons in the LHb.We found>30 ipsilateral and contralateral brain regions that projected to the LHb.Of these,there were significantly more monosynaptic LHb-projecting neurons from the lateral septum,anterior hypothalamus,dorsomedial hypothalamus,and ventromedial hypothalamus in females than in males.More interestingly,we found a stronger GABAergic projection from the medial septum to the LHb in males than in females.Our results reveal a comprehensive connectivity atlas of glutamatergic and GABAergic inputs to the LHb in both sexes,which may facilitate a better understanding of sexual dimorphism in physiological and pathological brain functions.
