Research Area: Physiology, Biophysics, Ionic channels, Connexins Hemichannels
PhD. In Biological Sciences (Physiology). Catholic University of Chile,, Santiago, Chile. (2008).
Bachelor in Biological Sciences, Faculty of Biological Sciences, Catholic University of Chile, Santiago, Chile.(2000)
E-mail: helmuth.sanchez at cinv.cl
Address: Centro Interdisciplinario de Neurociencia de Valparaíso.
Facultad de Ciencias, Universidad de Valparaíso.
Gran Bretaña 1111. Playa Ancha. Valparaíso. Chile.
Gap junctions channels (GJCs) communicate cytoplasm of two cells in contact. Each GJC is made of the union of two connexins hemichannels (Cx-HCs). In last years, it has been emerging evidence about the role of Cx-HCs in physiology and physiopathology as a direct high conductance pathway between cytoplasm and extracellular medium. Mutations that affect connexin genes could compromise Cx-HCs performance and be the cause of some diseases. My professional carrier has been focused in the study of Cx-HCs, trying to understand what conditions induce their opening and how correlate with increase of membrane permeability, loss of electrochemical gradients, and incidence of cell death. The goal of my current research is try to understand what biophysics changes induced by Cx26 mutations could explain phenotypes observed in skin-syndromic deafness disorders.
- Sanchez HA, Slavi N, Srinivas M and Verselis VK. Syndromic deafness mutations at Asn 14 differentially alter the open stability of Cx26 hemichannels. J Gen Physiol 148:25-42, 2016. PMCID: PMC4924935.
- Sanchez HA, Bienkowski R, Slavi N, Srinivas M and Verselis VK. Altered inhibition of Cx26 hemichannels by pH and Zn2+ in the A40V mutation associated with Keratitis-Ichthyosis-Deafness syndrome. J Biol Chem 289: 21519-21532, 2014. PMCID: PMC4118113.
- Sánchez HA, Villone K, Srinivas M and Verselis VK (2013). The D50N mutation and syndromic deafness: Altered Cx26 hemichannel properties caused by effects on the pore and intersubunit interactions. J Gen Physiol 142:3-22, 2013. PMCID:PMC3691445.
- Rubinos C, Sánchez HA, Verselis VK, Srinivas M (2012). Mechanism of inhibition of connexin channels by the quinine derivative N-benzylquininium. J Gen Physiol 139:69-82. PMCID:PMC3250100.
- Sánchez HA, Meşe G, Srinivas M, White TW and Verselis VK (2010). Differentially altered Ca2+ regulation and Ca2+ permeability in Cx26 hemichannels formed by the A40V and G45E mutations that cause Keratitis-Ichthiosis-Deafness Syndrome. J Gen Physiol 136: 47-62. PMCID:PMC2894548.
- Schalper KA, Sánchez HA, Lee SC, Altenberg GA, Nathanson MH and Sáez JC (2010). Connexin 43 hemichannels mediate the Ca2+ influx induced by extracellular alkalinization. Am J Physiol Cell Physiol 299: C1504–C1515. PMCID:PMC3774097.
- Sánchez HA, Orellana JA, Verselis VK and Sáez JC (2009). Metabolic inhibition increases activity of connexin-32 hemichannels permeable to Ca2+ in transfected HeLa cells. Am J Physiol Cell Physiol 297: C665–C678. PMCID:PMC2740400.
- Eugenín EA, González HE, Sánchez HA, Brañes MC and Sáez JC (2007). Inflammatory conditions induce gap junctional communication between rat Kupffer cells both in vivo and in vitro. Cell Immunol 247:103–110. PMCID:PMC2105790.
- Contreras JE, Sánchez HA, Eugenín EA, Speidel D, Theis M, Willecke K, Bukauskas FF, Bennett MVL and Sáez JC (2002). Metabolic inhibition induces opening of unapposed connexin43 gap junction hemichannels and reduces gap junctional communication in cortical rat astrocytes in culture. Proc Natl Acad Sci USA 99: 495-500. PMCID:PMC117588.
- Sanchez HA, Verselis VK. Aberrant Cx26 hemichannels and keratitis-ichthyosis-deafness syndrome: insights into syndromic hearing loss (2014) Front Cell Neurosci 8:354. PMCID: PMC4209889.
- Orellana JA, Sánchez HA, Schalper KA, Figueroa V, Sáez JC. Regulation of intercellular calcium signaling through calcium interactions with connexin-based channels (2012). Adv Exp Med Biol 740: 777-794. PMID:22453969.
- Orellana JA, Figueroa XF, Sánchez HA, Contreras-Duarte S, Velarde V, Sáez JC (2011). Hemichannels in the neurovascular unit and white matter under normal and inflamed conditions. CNS Neurol Disord Drug Targets 10(3): 404-414. PMID:21288190.
- Contreras JE, Sánchez HA, Véliz LP, Bukauskas FF, Bennett MVL and Sáez JC (2004). Role of connexin-based gap junction channels and hemichannels in ischemia-induced cell death in nervous tissue. Brain Res Rev 47: 290–303. PMCID:PMC3651737.