Biology subjects

Bello, O.

Publications and source records attributed to Bello, O..

2 recordsLinked to original sources

bioRxiv2025

Diploid potato lines for the study and improvement of starch metabolism and structure

Diploid potato breeding enables faster genetic improvement via selection against deleterious alleles in inbred lines, unlike breeding by intercrossing tetraploid varieties. Starch is the major source of calories in potato tubers, but the starch properties of diploid lines have rarely been reported. In this study, we provide a comprehensive characterisation of tuber and starch properties in two diploid lines that are early isolates from the Solynta breeding program, B26 and B100, and their F1 hybrids. B100 produced fewer, but larger tubers compared to B26, and both diploid lines produced tubers that are smaller than the tetraploid variety, Clearwater Russet. The low tuber yield of B100 correlates with its high self-compatibility and fruit production. Pruning of fruits in B100 significantly increased total tuber yield per plant by stimulating more tuber initiations, but had no effect on average tuber weight, starch content or starch structure. Among the diploid, hybrid and tetraploid lines examined, there were no differences in the total starch content of tubers. Although amylopectin structure and amylose content were similar between the two diploid lines and the tetraploid comparison, B26 had elevated levels of resistant starch and a striking elongated granule morphology. Our results showcase the variation in source-sink relations and starch structure in diploid potato breeding material, demonstrating their potential for research into the genetics underpinning metabolic and quality traits.

plant biology↗

bioRxiv2025

Bioelectric and Epigenetic Landscapes in Lateralized Breast Tumors Reveal Distinct Tumor Microenvironment Signatures.

Breast cancer heterogeneity is shaped not only by intrinsic tumor properties but by the surrounding microenvironment (TME). Here we report a left-right (L-R) asymmetry in the breast TME associated to tumor features. Bioinformatic analysis of TCGA RNA-seq and histological data revealed that R-sided tumors display higher stromal scores and are cancer-associated fibroblasts (CAFs) signatures. This difference was validated in paired L-R PDX and xenograft models, in which R-sided tumors showed increased -SMA expression. The asymmetry extended to tumor bioelectricity: across PDX and xenograft models, and in cells cultured with L- or R-conditioned media, L-sided tumors consistently displayed a more depolarized membrane potential than their R counterparts. In vitro, this bioelectric difference was methylation-dependent - abolished by the DNA methyltransferase inhibitor decitabine -and reversible when the laterality of the conditioned media was inverted. Methylome analysis of animal models identified the gap--unction gene GJA1 as significantly hypermethylated in L-sided tumors, accompanied by reduced expression of connexin genes. A computational model showed that membrane potential and methylation form two stable states, depending on gap-junction coupling strength. Together, these findings identify L-R asymmetry as an overlooked layer of breast tumor heterogeneity that integrates stromal, bioelectric, and epigenetic features. This framework may extend to other paired organs and suggests that tumor laterality could have biological and therapeutic relevance.

cancer biology↗