Alejandro obtained a BSc (Hons) in Marine Biology in Colombia at the University Tadeo Lozano. He moved later to Australia to do a PhD at the school of Molecular Sciences under the supervision of Prof. David Miller. In 2008, Alejandro joined Monica Medina’s research group at the University of California (Merced) as a postdoctoral fellow. Alejandro’s research has focused on the molecular mechanisms regulating metamorphosis and early calcification in the scleractinian corals Acropora millepora and Montastraea faveolata. He is interested in the study of the cellular processes regulating skeleton deposition in reef-building corals and their role in adaptation to climate change.
The coral skeleton consists of calcium carbonate (CaCO3) deposited upon an organic matrix primarily as aragonite. Currently galaxin, from Galaxea fascicularis, is the only soluble organic matrix component that has been characterized from a coral. Three genes related to galaxin were identified in the coral Acropora millepora. One of the Acropora genes (Amgalaxin) encodes a clear galaxin ortholog, while the others (Amgalaxin-like 1 and Amgalaxin-like 2) encode larger and more divergent proteins. All three proteins are predicted to be extracellular and share common structural features, most notably the presence of repetitive motifs containing dicysteine residues. In situ hybridisation reveals distinct, but partially overlapping, spatial expression of the genes in patterns consistent with distinct roles in calcification. Both of the Amgalaxin-like genes are expressed exclusively in the early stages of calcification, while Amgalaxin continues to be expressed in the adult, consistent with the situation in the coral Galaxea.