Biology subjects

Martinez, A. M.

Publications and source records attributed to Martinez, A. M..

3 recordsLinked to original sources

bioRxiv2024

Sugarcane carries relatively larger family of CAMTA transcription factors, active against drought stress

As the highly demanding complex genome of the hybrid sugarcane cultivar became publicly available last year (2023), it opened avenues to further study this important crop at molecular level. We are interested in digging the multiple stress responsive transcription factors family, the Calmodulin-Binding Transcription Activator (CAMTA) of sugarcane. This manuscript presents a comprehensive study of ScCAMTA family based on the latest sugarcane genome sequence information. Within the 10 gb genome, through HMM model prepared from sorghum CAMTA common domains, we found 48 genes, 46 out of which carry all the CAMTA-associated domains including CG-1, TIG, IQ and Ank. The phylogenetic analysis clustered then into seven classes. Keeping sorghum as reference, we named them as ScCAMTA1 - ScCAMTA7, while each one representing a class having 5-7 copies such as ScCAMTA1A - ScCAMTA1E, present in each sub-genome (chromosome) within the hybrid sugarcane. In parallel to determining their physico-chemical attributes, gene structure, promoter sequences, protein domains, miRNA targets, protein interaction network, GO, genome collinearity, their expression pattern against drought was determined using the RNAseq data which flaunted that ScCAMTA7 is highly active under drought. This study furthers the insights into complex sugarcane genome and will assist in developing its drought-tolerant varieties.

bioinformatics↗

bioRxiv2024

Treadmill step training promotes corticospinal tract plasticity after incomplete spinal cord injury

Spinal cord injury (SCI) often impairs motor functions such as voluntary movement and fine motor control, with the corticospinal tract (CST) being a crucial pathway affected. While CST-targeted rehabilitation, such as treadmill training, supports motor recovery, gaps remain in understanding the topographical changes within the CST and how they correlate with behavioral outcomes. In this study, we utilized a custom Emx1Cre;LSL-SynGFP mouse line to quantify CST plasticity following moderate contusion SCI, both with and without exercise (treadmill) training. Fluorescent labeling of cortical synapses allowed for detailed visualization of descending CST rewiring, and we assessed its relationship to behavioral outcomes, including kinematics analysis and motivational state. Mice were stratified by motivational state using the Progressive Ratio Assay, and locomotor recovery was evaluated through the Basso Mouse Scale (BMS), joint/limb kinematics, and Motion Sequencing (MoSeq) analysis. Our findings indicate that treadmill training enhances CST rewiring, especially in highly motivated animals, leading to increased synaptic density in the ventral horn and improved BMS subscores. Motivation further influenced specific kinematic parameters, such as toe clearance, while treadmill training significantly improved speed by reducing the stance phase. Results suggest that while treadmill training induces broad beneficial outcomes, motivation may fine-tune recovery, influencing neural circuit and behavioral changes. This suggests multiple mechanisms converge to promote recovery--those we cannot control and those we can. These results underscore the combined role of task-specific training and also perhaps motivation in driving CST plasticity and functional recovery after SCI.

neuroscience↗

bioRxiv2023

Using behavioral biomarkers to redefine epochs of spontaneous recovery following spinal cord injury

The brain-spinal cord axis generates movement by assembling motor primitives into coordinated sequences. Spinal cord injury (SCI) disrupts this neuroaxis, impairing not only locomotion, but the full repertoire of behavior. Traditional scales for quantifying recovery collapse this complexity into predefined locomotor-focused criteria that obscure heterogeneity in recovery. To quantify the full behavioral repertoire following SCI, we adapted motion sequencing (MoSeq) to identify sub-second behavioral "syllables" and capture their usage and sequential organization without predefined features. We identified biomechanically distinct variants within syllable classes that are shared across injury severities and found that recovery is jointly structured by injury severity and individual mouse identity. Changes in sequences, however, unfold along a conserved temporal trajectory. By compressing behavior into a single metric, we uncovered clusters of coevolving locomotor and non-locomotor behaviors. These results frame SCI recovery with repertoire-level changes, where adaptive strategies emerge from constrained access to motor primitives and their sequences.

neuroscience↗