Welcome to Machaca Lab!
I hope this site will provide you with an introduction to the people and ongoing projects in the Lab. Our philosophy is that science should be enjoyable and we certainly have lots of fun working together and solving questions of interest.
We are fascinated by the regulation of Ca2+ signaling pathways under both physiological and pathological conditions. Intracellular Ca2+ transients represent a ubiquitous signaling module throughout phylogeny that is critical in mediating cellular responses to various cues. We are particularly interested in how Ca2+ signaling modules are remodeled during cellular development and cellular pathology.
We employ several model systems to address these questions. The frog oocyte has been a favorite system in the Lab as it provides unique advantages. We focus on the remodeling of Ca2+signaling pathways during oocyte maturation in preparation for fertilization, where Ca2+ is the universal signal for egg activation and for mediating the egg–to–embryo transition. Over the years we have focused on specific Ca2+ signaling modules including the IP3 receptor, the store-operated Ca2+ entry pathway (STIM and Orai), the plasma membrane Ca2+ ATPase, and the Ca2+–activated Cl- channels (CaCC). These studies have now progressed to the mouse oocyte where we are assessing the phylogenetic conservation of the developmental regulation of Ca2+ signaling remodeling during meiosis. Following the theme of Ca2+ signaling remodeling, we are also exploring modulation of IP3–dependent Ca2+ release in vascular smooth muscle cells as a potential contributor to hypertension development.
The store–operated Ca2+ entry (SOCE) pathway is of particular interest in the Lab where we are interested in understanding the basic regulation of SOCE and how this Ca2+ influx pathway contributes to encoding specific cellular response.
Another emphasis in the Lab is on the mechanisms controlling the initiation of Xenopus oocyte maturation. In particular current efforts are focused on understanding the role of protein trafficking on the induction of maturation by progesterone and the involvement of G–protein coupled receptors in the process.
The Lab is also interested in the regulation of cell cycle progression by transition metals (Cu and Zn). This is in the context of both meiosis and mitosis. In meiosis we are interested in the regulation of dual specificity phosphatase Cdc25C by Zn. In the context of the mitotic cell cycle we are focusing of the role of transition metal chelation and the production of reactive oxygen species as a mechanism to interfere with the uncontrolled cell cycle in cancer cells.
As is clear from this brief summary, the Lab works on diverse area of cell biology and as such offers a vibrant environment for students and postdoctoral fellows to hone in their cell biological expertise.