File Download

There are no files associated with this item.

Conference Paper: Axonal trafficking of heparanase 1

TitleAxonal trafficking of heparanase 1
Authors
Issue Date2016
PublisherThe University of Hong Kong.
Citation
The 2016 Neuroscience Symposium and Annual Scientific Conference of the Hong Kong Society of Neurosciences, The University of Hong Kong, Hong Kong, 18 May 2016. In Programme Book, 2016, p. 41, abstract no. P25 How to Cite?
AbstractHeparanase 1 (HPA1) is the mammalian β-D-endoglycosidase that degrades heparan sulfate (HS). It is synthesized as a latent form (proheparanase) that lacks enzymatic activity. Proheparanase will be secreted to the extracellular environment before it is reuptake by the cells via heparan sulfate proteoglycan (HSPG). The internalized proheparanase will then be processed to the mature form that displays enzymatic activity in lysosome. Neurons, unlike other mammalian cells, have highly arborized morphology. However, it is still unknown how neuronal heparanase may be transported and processed. In cultured hippocampal neuros, we found axonal localization of heparanase 1. Axonal heparanase distributes along the neurofilament as shown by image from structure illumination microscopy, suggesting its active axonal trafficking, which was further confirmed by the presynaptic rather than postsynaptic localization of heparanase. Similar to other mammalian cells, neuronal heparanase, predominantly the latent form, can also be released. The exocytosed heparanase however, show low affinity for heparin. In addition, we found, unexpectedly, that even the purified recombinant heparanase, when exogenously added, fail to bind to heparan sulfate at the cell surface significantly, indicating that heparanase may not be extensively internalized by the neurons. This is confirmed by sparse co-localization between heparanase and early endosome. Additionally, we also identified the activity-regulated expression of HPA1. Specifically, long term suppression or increase of neuronal activity will result in decrease of increase of HPA1 expression respectively. Collectively, our data suggests a novel trafficking pathway of HPA1 and suggest that HPA1 may be involved in the process of homeostatic plasticity.
DescriptionConference Theme: Nature and Nurture in Brain Functions
Persistent Identifierhttp://hdl.handle.net/10722/231500

 

DC FieldValueLanguage
dc.contributor.authorLi, ZH-
dc.contributor.authorLam, YL-
dc.contributor.authorMa, CW-
dc.contributor.authorChan, YS-
dc.contributor.authorShum, DKY-
dc.date.accessioned2016-09-20T05:23:34Z-
dc.date.available2016-09-20T05:23:34Z-
dc.date.issued2016-
dc.identifier.citationThe 2016 Neuroscience Symposium and Annual Scientific Conference of the Hong Kong Society of Neurosciences, The University of Hong Kong, Hong Kong, 18 May 2016. In Programme Book, 2016, p. 41, abstract no. P25-
dc.identifier.urihttp://hdl.handle.net/10722/231500-
dc.descriptionConference Theme: Nature and Nurture in Brain Functions-
dc.description.abstractHeparanase 1 (HPA1) is the mammalian β-D-endoglycosidase that degrades heparan sulfate (HS). It is synthesized as a latent form (proheparanase) that lacks enzymatic activity. Proheparanase will be secreted to the extracellular environment before it is reuptake by the cells via heparan sulfate proteoglycan (HSPG). The internalized proheparanase will then be processed to the mature form that displays enzymatic activity in lysosome. Neurons, unlike other mammalian cells, have highly arborized morphology. However, it is still unknown how neuronal heparanase may be transported and processed. In cultured hippocampal neuros, we found axonal localization of heparanase 1. Axonal heparanase distributes along the neurofilament as shown by image from structure illumination microscopy, suggesting its active axonal trafficking, which was further confirmed by the presynaptic rather than postsynaptic localization of heparanase. Similar to other mammalian cells, neuronal heparanase, predominantly the latent form, can also be released. The exocytosed heparanase however, show low affinity for heparin. In addition, we found, unexpectedly, that even the purified recombinant heparanase, when exogenously added, fail to bind to heparan sulfate at the cell surface significantly, indicating that heparanase may not be extensively internalized by the neurons. This is confirmed by sparse co-localization between heparanase and early endosome. Additionally, we also identified the activity-regulated expression of HPA1. Specifically, long term suppression or increase of neuronal activity will result in decrease of increase of HPA1 expression respectively. Collectively, our data suggests a novel trafficking pathway of HPA1 and suggest that HPA1 may be involved in the process of homeostatic plasticity.-
dc.languageeng-
dc.publisherThe University of Hong Kong.-
dc.relation.ispartofNeuroscience Symposium & Annual Scientific Conference of the Hong Kong Society of Neurosciences-
dc.titleAxonal trafficking of heparanase 1-
dc.typeConference_Paper-
dc.identifier.emailLam, YL: annalyl@hku.hk-
dc.identifier.emailMa, CW: cwma2010@hku.hk-
dc.identifier.emailChan, YS: yschan@hku.hk-
dc.identifier.emailShum, DKY: shumdkhk@hkucc.hku.hk-
dc.identifier.authorityChan, YS=rp00318-
dc.identifier.authorityShum, DKY=rp00321-
dc.identifier.hkuros266286-
dc.identifier.spage41, abstract no. P25-
dc.identifier.epage41, abstract no. P25-
dc.publisher.placeHong Kong-

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats