Although much is known about how axons and dendrites are guided to a target tissue, little is understood regarding how pre- and postsynaptic partners are matched for synapse formation. The zebrafish lateral line offers the opportunity for greater insight into this process. Hair cells in the lateral-line neuromast exist as two intermingled subpopulations, anteriorly and posteriorly polarized cells. Afferent neurons form synapses with hair cells of only one subpopulation, and this polarity-specific innervation arises independently of synaptic activity. The research presented in my thesis deepens the understanding of synapse formation in the zebrafish lateral line. First, I examine the neuronal architecture of the neuromast at nanometer-scale resolution by imaging the tissue by serial block-face electron microscopy. The data demonstrate that afferent neurons show a polarity preference at the earliest stages of hair-cell innervation, and additionally that the synaptic arrangement appears to arise from interactions among neurons for access to synaptic ribbons rather than being mediated by an accessory cell. I next describe a novel phenomenon, the extension of transient, dynamic projections from the base of nascent hair cells beginning shortly after mitosis. The projections extend toward nearby mature hair-cell synapses and filopodia arising from afferent terminals extend directly along them toward unoccupied synaptic ribbons. Hair-cell projections lacking stable association of afferent neurons are larger than those that are stably innervated. The appearance of hair-cell projections is contemporaneous with the initiation of contact between afferent neurons and nascent hair cells, and the disappearance of projections coincides with the appearance of pre- and postsynaptic markers proteins. I propose a model in which hair-cell projections act as cellular scaffolds for the guidance of neurons to available synaptic sites. Finally, I describe a novel method for collecting subpopulations of cells for gene expression analysis, which I employ to compare the transcriptomes of anteriorly and posteriorly polarized hair cells. I identified a number of differentially expressed candidate genes that might mediate polarity-specific afferent innervation. This work expands the repertoire of tools available for investigations of the neuromast and enhances the understanding of synapse formation in the zebrafish lateral line.
","abstract_html":"<p>Although much is known about how axons and dendrites are guided to a target tissue, little is understood regarding how pre- and postsynaptic partners are matched for synapse formation. The zebrafish lateral line offers the opportunity for greater insight into this process. Hair cells in the lateral-line neuromast exist as two intermingled subpopulations, anteriorly and posteriorly polarized cells. Afferent neurons form synapses with hair cells of only one subpopulation, and this polarity-specific innervation arises independently of synaptic activity. The research presented in my thesis deepens the understanding of synapse formation in the zebrafish lateral line. First, I examine the neuronal architecture of the neuromast at nanometer-scale resolution by imaging the tissue by serial block-face electron microscopy. The data demonstrate that afferent neurons show a polarity preference at the earliest stages of hair-cell innervation, and additionally that the synaptic arrangement appears to arise from interactions among neurons for access to synaptic ribbons rather than being mediated by an accessory cell. I next describe a novel phenomenon, the extension of transient, dynamic projections from the base of nascent hair cells beginning shortly after mitosis. The projections extend toward nearby mature hair-cell synapses and filopodia arising from afferent terminals extend directly along them toward unoccupied synaptic ribbons. Hair-cell projections lacking stable association of afferent neurons are larger than those that are stably innervated. The appearance of hair-cell projections is contemporaneous with the initiation of contact between afferent neurons and nascent hair cells, and the disappearance of projections coincides with the appearance of pre- and postsynaptic markers proteins. I propose a model in which hair-cell projections act as cellular scaffolds for the guidance of neurons to available synaptic sites. Finally, I describe a novel method for collecting subpopulations of cells for gene expression analysis, which I employ to compare the transcriptomes of anteriorly and posteriorly polarized hair cells. I identified a number of differentially expressed candidate genes that might mediate polarity-specific afferent innervation. This work expands the repertoire of tools available for investigations of the neuromast and enhances the understanding of synapse formation in the zebrafish lateral line.</p>","abstract_has_math":false,"creators":["Dow, Eliot"],"institution":null,"degree_name":"Doctor of Philosophy (PhD)","degree_level":"Thesis","degree_discipline":null,"degree_department":null,"school":null,"contributors":["A. James Hudspeth"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2015,"date_issued":"2015-01-01T08:00:00Z","date_published":"2015-01-01T08:00:00Z","updated_at":"2026-07-24T04:11:45Z","subjects":["synapse formation","zebrafish lateral line","hair-cell polarity","afferent innervation","neuronal projections","gene expression analysis","Life Sciences"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://digitalcommons.rockefeller.edu/student_theses_and_dissertations/277","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["A. James Hudspeth"]},{"key":"dc:creator","label":"Author","values":["Dow, Eliot"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Doctor of Philosophy (PhD)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["synapse formation","zebrafish lateral line","hair-cell polarity","afferent innervation","neuronal projections","gene expression analysis","Life Sciences"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://digitalcommons.rockefeller.edu/student_theses_and_dissertations/277"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Although much is known about how axons and dendrites are guided to a target tissue, little is understood regarding how pre- and postsynaptic partners are matched for synapse formation. The zebrafish lateral line offers the opportunity for greater insight into this process. Hair cells in the lateral-line neuromast exist as two intermingled subpopulations, anteriorly and posteriorly polarized cells. Afferent neurons form synapses with hair cells of only one subpopulation, and this polarity-specific innervation arises independently of synaptic activity. The research presented in my thesis deepens the understanding of synapse formation in the zebrafish lateral line. First, I examine the neuronal architecture of the neuromast at nanometer-scale resolution by imaging the tissue by serial block-face electron microscopy. The data demonstrate that afferent neurons show a polarity preference at the earliest stages of hair-cell innervation, and additionally that the synaptic arrangement appears to arise from interactions among neurons for access to synaptic ribbons rather than being mediated by an accessory cell. I next describe a novel phenomenon, the extension of transient, dynamic projections from the base of nascent hair cells beginning shortly after mitosis. The projections extend toward nearby mature hair-cell synapses and filopodia arising from afferent terminals extend directly along them toward unoccupied synaptic ribbons. Hair-cell projections lacking stable association of afferent neurons are larger than those that are stably innervated. The appearance of hair-cell projections is contemporaneous with the initiation of contact between afferent neurons and nascent hair cells, and the disappearance of projections coincides with the appearance of pre- and postsynaptic markers proteins. I propose a model in which hair-cell projections act as cellular scaffolds for the guidance of neurons to available synaptic sites. Finally, I describe a novel method for collecting subpopulations of cells for gene expression analysis, which I employ to compare the transcriptomes of anteriorly and posteriorly polarized hair cells. I identified a number of differentially expressed candidate genes that might mediate polarity-specific afferent innervation. This work expands the repertoire of tools available for investigations of the neuromast and enhances the understanding of synapse formation in the zebrafish lateral line.
"]},{"key":"dc:title","label":"Title","values":["Synapse Formation in the Zebrafish Lateral Line"]}]}],"canonical_facts":{"dc:contributor":["A. James Hudspeth"],"dc:creator":["Dow, Eliot"],"dc:description.abstract":["Although much is known about how axons and dendrites are guided to a target tissue, little is understood regarding how pre- and postsynaptic partners are matched for synapse formation. The zebrafish lateral line offers the opportunity for greater insight into this process. Hair cells in the lateral-line neuromast exist as two intermingled subpopulations, anteriorly and posteriorly polarized cells. Afferent neurons form synapses with hair cells of only one subpopulation, and this polarity-specific innervation arises independently of synaptic activity. The research presented in my thesis deepens the understanding of synapse formation in the zebrafish lateral line. First, I examine the neuronal architecture of the neuromast at nanometer-scale resolution by imaging the tissue by serial block-face electron microscopy. The data demonstrate that afferent neurons show a polarity preference at the earliest stages of hair-cell innervation, and additionally that the synaptic arrangement appears to arise from interactions among neurons for access to synaptic ribbons rather than being mediated by an accessory cell. I next describe a novel phenomenon, the extension of transient, dynamic projections from the base of nascent hair cells beginning shortly after mitosis. The projections extend toward nearby mature hair-cell synapses and filopodia arising from afferent terminals extend directly along them toward unoccupied synaptic ribbons. Hair-cell projections lacking stable association of afferent neurons are larger than those that are stably innervated. The appearance of hair-cell projections is contemporaneous with the initiation of contact between afferent neurons and nascent hair cells, and the disappearance of projections coincides with the appearance of pre- and postsynaptic markers proteins. I propose a model in which hair-cell projections act as cellular scaffolds for the guidance of neurons to available synaptic sites. Finally, I describe a novel method for collecting subpopulations of cells for gene expression analysis, which I employ to compare the transcriptomes of anteriorly and posteriorly polarized hair cells. I identified a number of differentially expressed candidate genes that might mediate polarity-specific afferent innervation. This work expands the repertoire of tools available for investigations of the neuromast and enhances the understanding of synapse formation in the zebrafish lateral line.
"],"dc:identifier":["https://digitalcommons.rockefeller.edu/student_theses_and_dissertations/277"],"dc:subject":["synapse formation","zebrafish lateral line","hair-cell polarity","afferent innervation","neuronal projections","gene expression analysis","Life Sciences"],"dc:title":["Synapse Formation in the Zebrafish Lateral Line"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["Doctor of Philosophy (PhD)"]},"updated_at":"2026-07-24T04:11:45Z"}