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Biology subjects

Lombardo, F.

Publications and source records attributed to Lombardo, F..

3 recordsLinked to original sources

Fine-Tuning TAWAWA1-Mediated Panicle Architecture by Genome Editing of a Downstream Conserved Noncoding Sequence in Rice

Genome editing is a promising tool to enhance plant breeding, particularly for the generation of practical quantitative traits. We focused on the rice yield-related gene TAWAWA1 (TAW1) and produced various degrees of increased panicle branching phenotypes by modifying its downstream conserved noncoding sequence (CNS). Differential modification of two highly conserved regions containing putative repressive elements in this CNS caused transcriptional upregulation of TAW1, resulting in diverse phenotypes.

plant biology↗

Application of mechanistic multiparameter optimization and large scale in vitro to in vivo pharmacokinetics correlations to small molecule therapeutic projects

Computational chemistry and machine learning are used in drug discovery to predict target-specific and pharmacokinetic properties of molecules. Multiparameter optimization (MPO) functions are used to summarize multiple properties into a single score, aiding compound prioritization. However, over-reliance on subjective MPO functions risks reinforcing human bias. Mechanistic modeling approaches based on physiological relevance can be adapted to meet different potential key objectives of the project (e.g. minimizing dose, maximizing safety margins and/or minimized drug-drug interaction risk) while retaining the same underlying model structure. The current work incorporates recent approaches to predict in vivo PK properties and validates in vitro to in vivo correlation analysis to support mechanistic PK MPO. Examples of use and impact in small molecule drug discovery projects are provided. Overall, the mechanistic MPO identifies 83% of the compounds considered as short-listed for clinical experiments in the top 2nd percentile, and 100% in the top 10th percentile, resulting in an area under the receiver operating characteristic curve (AUCROC) > 0.95. In addition, the MPO score successfully recapitulates the chronological progression of the optimization process across different scaffolds. Finally, the MPO scores for compounds characterized in pharmacokinetics experiments are markedly higher compared to the rest of the compounds synthesized, highlighting the potential of this tool to reduce the reliance on in vivo testing for compound screening.

pharmacology and toxicology↗

Measuring the impact of genetic heterogeneity and chromosomal inversions on the efficacy of CRISPR-Cas9 gene drives in different strains of Anopheles gambiae

The human malaria vector Anopheles gambiae is becoming increasingly resistant to insecticides, spurring the development of genetic control strategies. CRISPR-Cas9 gene drives can modify a population by creating double-stranded breaks at highly specific targets, triggering copying of the gene drive into the cut site ( homing), ensuring its inheritance. The DNA repair mechanism responsible requires homology between the donor and recipient chromosomes, presenting challenges for the invasion of lab-developed gene drives into wild populations of target species An. gambiae species complex, which show high levels of genome variation. Two gene drives (vas2-5958 and zpg-7280) were introduced into three An. gambiae strains collected across Africa with 5.3-6.6% variation around the target sites, and the effect of this variation on homing was measured. Gene drive homing across different karyotypes of the 2La chromosomal inversion was also assessed. No decrease in gene drive homing was seen despite target site heterology, demonstrating the applicability of gene drives to wild populations.

genetics↗