Alteration of endoplasmic reticulum homeostasis imposes stress and subsequently leads to accumulation of unfolded or misfolded proteins in the reticulum lumen. The endoplasmic reticulum has evolved a highly specific signaling pathway called the unfolded protein response (UPR) to deal with the accumulation of unfolded or misfolded proteins. In yeast, endoplasmic reticulum stress is monitored by Ire1p. Under ER stress conditions, Ire1p suffers oligomerization through its lumenal domain which leads to trans-autophosphorylation via its C-terminal kinase domain, which in turn, activates the endonuclease domain. Ire1p splices the pre-mRNA of the HAC1 gene, which encodes a bZIP transcription factor that drives expression of UPR-responsive genes. A connection between the UPR pathway and the MAPK module that participates in the hiperosmotic response (the HOG pathway) has been deducted by the finding that inactivation of MAPK signaling components induce enhanced sensitivity to agents that impose endoplasmic reticulum stress.

In our laboratory we are interested in finding the molecular link between MAPK-mediated signaling pathways, with the UPR pathway in both, budding yeasts (Saccharomyces cerevisiae and Kluyveromyces lactis) and social amoeba Dictyostelium discoideum. While yeasts are unicellular organisms, Dictyostelium alternates between unicellular and multicellular stages. Dictyostelium is a model organism for studying central aspects of developmental biology like cell movement, cell type determination, spatial patterning, coordination between morphogenesis and gene expression, etc.

This is an original topic in which we take yeast and Dictyostelium as model organisms to increase knowledge about the molecular mechanisms involved in human diseases such as Parkinson, Alzheimer, etc.


Molecular Biology, Cell Biology, Recombinant DNA Technology, Traditional and Modern Genetics, Imaging Technologies (Light Microscopy, Confocal Microscopy, Electronic Microscopy), Cytometry, etc



              LAB MEMBERS


         Laura Kawasaki Watanabe ( Technician



            Edith Sánchez Paredes ( PhD student


            Nancy Velázquez Zavala ( PhD student



             Rocío Navarro Olmos   ( PhD student


         Miriam Rodríguez González ( PhD student


              Abril Escamilla Ayala                                (    undergraduate student


            Francisco Torres Quiroz ( PhD student



                     Olga Zurita

( Visiting student


                     Laura Ongay

      ( Researcher



Research interests






Links of interest:

Kuyveromyces lactis (

Saccharomyces cerevisiae (

Dictyostelium discoideum (


Biologist, Facultad de Ciencias, UNAM (1983). Masters Degree in Biomedical Research, UACPyP CCH, UNAM (1986). Ph D. in Biomedical Research, UACPyP CCH, UNAM (1989). Postdoctoral Fellow, Baylor College of Medicine, Houston TX (1989-1992). Full-time Professor at Instituto de Fisiología Celular, UNAM (since 1992).

Selected Publications

Kawasaki L., Castañeda-Bueno M., Sánchez-Paredes E., Velázquez-Zavala N., Torres-Quiroz F., Ongay-Larios L. and Coria R (2008) Protein Kinases involved in mating and osmotic stress in the yeast Kluyveromyces lactis. Eukaryotic Cell. 7 :78-85

Ongay-Larios L., Navarro-Olmos R., Kawasaki L., Velázquez-Zavala N., Sánchez-Paredes E., Torres-Quiroz F., Coello G. and Coria R (2007) Kluyveromyces lactis sexual pheromones. Gene structures and cellular responses to α-factor. FEMS Yeast Res. 7 :740-747

Torres-Quiroz F., Kawasaki L., Rodríguez-González M., Patrón-Soberano A. and Coria R. (2007) The KlSTE2 and KlSTE3 genes encode MATα and MATa specific G-protein-coupled receptors respectively which are required for mating of Kluyveromyces lactis haploid cells. Yeast. 24 :17-25

Coria R., Kawasaki L., Torres-Quiroz F., Ongay-Larios L., Sánchez-Paredes E., Velázquez-Zavala N., Navarro-Olmos R., Rodríguez-González M., Aguilar-Corachán R. and Coello G. (2006) The pheromone response pathway of Kluyveromyces lactis. FEMS Yeast Res. 6 :336-344

Michel, B., Lozano, C., Rodríguez, M., Coria R., Ramírez, J., and Peña, A. (2006) The yeast potassium transporter TRK2 is able to substitute for TRK1 in its biological function under low K+ and low pH conditions.. Yeast. 23 :581-589

Zhou, X-L., Loukin S.H., Coria R., Kung C. and Saimi Y. (2005) Heterologously expressed fungal TRP channels retain mechanosensitivity in vitro and osmotic response in vivo. Eur. Biophys. J. Biophy. 34 :413-422

Kawasaki, L., Saviñón-Tejeda A.L., Ongay-Larios L., Ramírez J. and Coria R. (2005) The G(KlSte4p) subunit of the heterotrimeric G protein has a positive and essential role in the induction of mating in the yeast Kluyveromyces lactis. Yeast. 22 :947-956

Alejandro Lloret, Alma Saviñón-Tejeda, Laura Ongay-Larios, Eda P. Tenorio and Roberto Coria (2003) The KlFUS1 gene is required for proper haploid mating and its expression is enhance by the active form of the Gα (Gpa1) subunit involved in the pheromone response pathway of the yeast Kluyveromyc. FEMS Microbiol Lett. 219 :105-113

Miranda M., Saldaña C., Ramírez J., Codiz G., Brunner L., Ongay-Larios L., Coria R and Peña A (2002) The KlTrk1 gene encodes a low affinity transporter of the K+ uptake system in the budding yeast Kluyveromyces lactis. Yeast.. 19 :601-609

Saldaña C., Naranjo D., Coria R., Peña A., and Vaca L. (2002) Splitting the two-pore-domains from TOK1 results in two potassium channels with novel functional properties. J. Biol. Chem.. 277 :4797-4805