Dr. Franklin Carrero-Martínez Dr. Franklin Carrero-Martínez

Adjunct Professor (Assistant Professor of Dept. of Biology, UPR Mayaguez)
Lab B148, B-167, B170, B175, Office B-204 (Dept. of Biology, UPR Mayaguez)
franklin.carrero@upr.edu
787-832-4040 x2405 x3923

Interests: Molecular, genetic and structural influences on the development of the neuromuscular junction in Drosophila melanogaster.

The long-term goal of my research program is motivated by several issues in cellular and molecular neuroscience: The understanding of molecular mechanisms underlying development, regulation and function of synapses. In pursuit of this goal, my research program is currently focused on the underlying signaling mechanisms involved in synaptic partner-induced postsynaptic filopodial clustering and the recruitment of cytoplasmic proteins to this subcellular space.

For centuries, a key question of interest to many has been how a synapse develops. Historically, muscles were thought to be passive structures that merely provided a substrate for the active axonal growth cone. However, we now know that faithful formation of synapses results from the precise spatiotemporal interactions of the molecular components responsible for target guidance and recognition, cytoskeletal remodeling and subsynaptic specialization.

This project investigates the in vivo cellular dynamics that are suspected to have major impacts on the process of synaptogenesis. Using the Drosophila neuromuscular junction as a model, my research attempts to gain a better understanding of the three-dimensional interactions in vivo between synaptic partners, which are currently unknown.

Available high-resolution bio-imaging techniques (GFP- and RFP-based bio-probes together with time-lapse confocal microscopy) allows me to perform in vivo analysis at high cellular resolutions using live, undissected organisms.This intact embryo context preserves the spatial three-dimensionality of those molecular and physical factors playing a role in axon guidance, target recognition and synaptogenesis. It also facilitates the study of mechanisms involved in brain organization within their native environment.

GFP (green fluorescent protein) and RFP (red fluorescent protein) tagged proteins are being visualized using different acquisition techniques. Depending on the purpose of the experiment, 2D time-lapse (high temporal resolution), 3D (high spatial resolution) or 4D (3D time-lapse; a hybrid level resolution) image stacks are acquired using inverted microscopes with either laser scanning or spinning-disc confocal modules. The image stacks are then analyzed using various 3D reconstruction and deconvolution software packages. In order to facilitate the organization of this site and to facilitate discussion of this highly specific and complicated developmental event, I have divided this part of my research in three main areas: (1) Myopodia (post-synaptic filopodia); (2) Neuromuscular synaptogenesis (Muscle Innervation); (3) Muscle Contraction. In summary, this project investigates the in vivo cellular dynamics that are suspected to have major impacts of the process of synaptogenesis. The results are anticipated to enhance our hitherto underappreciated cellular dynamics that surround, or perhaps even dictate the process of synaptogenesis.

Selected Publications:

Selected abstracts/presentations: