Biology subjects

Anzalone, A.

Publications and source records attributed to Anzalone, A..

3 recordsLinked to original sources

bioRxiv2026

Microtubule Stabilization and Biomaterial Guidance Synergize to Enhance CST Regeneration and Motor Recovery After Chronic SCI.

Spinal cord injury (SCI) results in loss of sensory and motor function below the level of damage, with chronic injuries presenting unique challenges for regenerative therapies. While multichannel biomaterial interventions have shown promise in promoting axonal regeneration, circuit restoration, and motor recovery in acute SCI, achieving similar outcomes in chronic injury models remains challenging due to a combination of intrinsic and extrinsic factors. These include the reduced capacity of the neuronal cell body to sustain a growth-activated state and the formation of a physical and chemical barrier at the injury site, preventing axonal growth. To address these challenges and promote motor recovery after chronic injury, we investigated the combinatorial effect of two regenerative approaches: 1) the implantation of poly (lactide-co-glycolide) (PLG) biomaterial bridge to guide axonal growth through the injury site, and 2) the delivery of Epothilone B (EpoB), a microtubule stabilizer that strengthens axons to promote regrowth. We used a transgenic mouse model that selectively expresses a red fluorescent protein variant (tdTomato) reporter throughout the corticospinal tract (CST) under control of the Crym promoter (Crym-tdTomato). We demonstrated that the combination of bridge implantation 60 days after surgical hemisection at C5 with EpoB improved locomotor function. At 12 weeks post-bridge implantation, immunohistology revealed axon regeneration in mice receiving implantation, but not EpoB or no-implant controls. The addition of EpoB significantly increased the volume of both total and CST axons regenerating through the biomaterial channels. Diffusion tensor magnetic resonance imaging (DTI) analysis identified enhanced fractional anisotropy (FA), axial diffusivity (AD), and mean diffusivity (MD) in the bridge region in the combination treatment group, consistent with new intact axons. Furthermore, EpoB enhanced the myelination of regenerated axons in the bridge. Finally, we investigated the proteomic profile of corticospinal neurons ipsilateral and contralateral to the SCI lesion and bridge, comparing the effect of EpoB treatment. Mass spectrometry-based analysis of laser-captured cells in this paradigm identified activation of a regeneration program by corticospinal neurons. These findings present a novel approach to enhance regenerative neural repair and locomotor recovery in chronic SCI.

neuroscience↗

bioRxiv2024

Genomic Insights and Biocontrol Potential of Ten Bacterial Strains from the Tomato Core Microbiome

Despite their adverse environmental effects, modern agriculture relies heavily on agrochemicals to manage diseases and pests and enhance plant growth and productivity. Some of these functions could instead be fulfilled by endophytes from the plant microbiota, which have diverse activities beneficial for plant growth and health. We therefore used a microbiome-guided top-down approach to select ten bacterial strains from different taxa in the core microbiome of tomato plants in the production chain for evaluation as potential bioinoculants. These taxa included some that are commonly used as biofertilizers and biocontrol agents (Pseudomonas and Bacillus) as well as the less studied genera Leclercia, Chryseobacterium, Glutamicibacter, and Paenarthorbacter. When inoculated in the tomato rhizosphere, these strains promoted plant growth and reduced the severity of Fusarium Crown and Root Rot and Bacterial Spot infections. High-quality genomes for each strain were obtained using Oxford Nanopore long-read and Illumina short-read sequencing, enabling the dissection of their genetic makeup to identify phyto-beneficial traits. This yielded a comprehensive inventory of genes from each strain related to processes including colonization, biofertilization, phytohormones, and plant signaling. Traits directly relevant to fertilization including phosphate solubilization and acquisition of nitrogen and iron were also identified. Moreover, the strains carried several functional genes putatively involved in abiotic stress alleviation and biotic stress management, traits that indirectly foster plant health and growth. The gathered genomic information will be instrumental in planning the use of these bacteria individually or in consortia to enhance plant growth by coupling strains with different traits, effects, and mechanisms of action.

genomics↗

bioRxiv2021

Programmable large DNA deletion, replacement, integration, and inversion with twin prime editing and site-specific recombinases

The targeted deletion, replacement, integration, or inversion of DNA sequences at specified locations in the genome could be used to study or treat many human genetic diseases. Here, we describe twin prime editing (twinPE), a method for the programmable replacement or excision of DNA sequence at endogenous human genomic sites without requiring double-strand DNA breaks. TwinPE uses a prime editor (PE) protein and two prime editing guide RNAs (pegRNAs) that template the synthesis of complementary DNA flaps on opposing strands of genomic DNA, resulting in the replacement of endogenous DNA sequence between the PE-induced nick sites with pegRNA-encoded sequences. We show that twinPE in human cells can perform precise deletions of at least 780 bp and precise replacements of genomic DNA sequence with new sequences of at least 108 bp. By combining single or multiplexed twinPE with site-specific serine recombinases either in separate steps or in a single step, we demonstrate targeted integration of gene-sized DNA plasmids (>5,000 bp) into safe-harbor loci including AAVS1, CCR5, and ALB in human cells. To our knowledge, these results represent the first RNA-programmable insertion of gene-sized DNA sequences into targeted genomic sites of unmodified human cells without requiring double-strand breaks or homology-directed repair. Twin PE combined with recombinases also mediated a 40,167-bp inversion at IDS that corrects a common Hunter syndrome allele. TwinPE expands the capabilities of precision gene editing without requiring double-strand DNA breaks and synergizes with other tools to enable the correction or complementation of large or complex pathogenic alleles in human cells.

genomics↗