Whole genome sequencing-based multi-locus association mapping for kernel iron, zinc and protein content in groundnut
Authors: Sagar, U. N., Parmar, S., Gangurde, S. S., Sharma, V., Pandey, A. K., Mohinuddin, D. K., Dube, N., Bhat, R. S., John, K., Sreevalli, M. D., Rani, P. S., Singh, K., Varshney, R. K., Pandey, M. K.
The study used multi‑season phenotyping for iron, zinc, and protein content together with whole‑genome re‑sequencing of a groundnut mini‑core collection to conduct a genome‑wide association study, identifying numerous marker‑trait associations and candidate genes linked to nutrient homeostasis. SNP‑based KASP markers were designed for nine loci, of which three showed polymorphism and are ready for deployment in genomics‑assisted breeding for nutrient‑rich groundnut varieties.
The study integrates genome, transcriptome, and chromatin accessibility data from 380 soybean accessions to dissect the genetic and regulatory basis of symbiotic nitrogen fixation (SNF). Using GWAS, TWAS, eQTL mapping, and ATAC-seq, the authors identify key loci, co‑expression modules, and regulatory elements, and validate the circadian clock gene GmLHY1b as a negative regulator of nodulation via CRISPR and CUT&Tag. These resources illuminate SNF networks and provide a foundation for soybean improvement.
The study generated a phenotypic dataset for 550 Lactuca accessions, including 20 wild relatives, and applied an iterative two‑step GWAS using a jointly processed SNP set for cultivated lettuce (L. sativa) and its wild progenitor (L. serriola) to dissect trait loci. Known and novel QTLs for anthocyanin accumulation, leaf morphology, and pathogen resistance were identified, with several L. serriola‑specific QTLs revealing unique genetic architectures, underscoring the breeding value of wild lettuce species.
The study used chlorophyll fluorescence imaging to map non-photochemical quenching (NPQ) gradients along barley leaf axes and found heat stress attenuates NPQ induction, revealing spatial heterogeneity in stress responses. Genome‑wide association and transcriptomic analyses identified candidate genes, notably HORVU.MOREX.r3.3HG0262630, that mediate region‑specific heat responses, highlighting pathways for improving cereal heat resilience.
Modulation of the GT Family 47 clade B gene affects arabinan deposition in elaters of Marchantia polymorpha
Authors: Kang, H. S. F., Lampugnani, E. R., Tong, X., Prabhakar, P. K., Flores-Sandoval, E., Hansen, J., Jorgensen, B., Bowman, J. L., Urbanowicz, B. R., Ebert, B., Persson, S.
The study investigates the function of two GT47B arabinan arabinosyltransferases in the liverwort Marchantia polymorpha, generating loss‑of‑function and overexpression lines to assess cell wall composition. Using CoMPP, glycosyl linkage analysis, and LM6 immunolabelling, the authors found that MpARADL2 mutants have reduced 1,5‑L‑arabinan epitopes in elaters despite unchanged overall 5‑linked Araf levels, suggesting additional enzymes compensate in thallus tissue. Attempts to express and purify the enzymes in HEK293 cells failed, implying a clade‑specific solubility requirement and highlighting the need to identify interacting partners.
The Building Blocks of Early Land Plants: Glycosyltransferases and Cell Wall Architecture in the model liverwort Marchantia polymorpha
Authors: Kang, H. S. F., Tong, X., Mariette, A., Leong, M., Beahan, C., Flores-Sandoval, E., Pedersen, G., Rautengarten, C., Bowman, J. L., Ebert, B., Bacic, A., Doblin, M., Persson, S., Lampugnani, E. R.
The study characterizes the composition and structure of cell wall glycans in eight tissue types of the liverwort Marchantia polymorpha, revealing both typical land‑plant features and unique traits such as abundant (1,5)-arabinan in sporophytes and low overall pectin levels. Comparative genomic analysis shows a diversified glycosyltransferase repertoire relative to Arabidopsis, and the authors created a Gateway‑compatible library of 93 M. polymorpha GTs to facilitate future functional studies.
The authors identified MpCAFA, a protein combining CAPS-like and FAP115-like domains, as a key factor for rapid ciliary swimming in the liverwort Marchantia polymorpha spermatozoids. Loss-of-function mutants displayed markedly reduced swimming speed despite normal axoneme structure, chemotaxis, and fertility, and these defects were rescued by a MpCAFA‑mCitrine fusion that localized along the entire cilium. Both the CAPS-like and FAP115-like regions are required for MpCAFA’s function and ciliary targeting, establishing it as a major ciliary protein and a marker for visualizing spermatozoid motility.
The study investigated meristem activation in the liverwort Marchantia polymorpha, revealing that simulated shade causes alternating inactivity of meristems. Transcriptomic comparison of active versus inactive meristems identified the cytochrome P450 monooxygenase MpCYP78E1 as an inhibitor of meristem activity and initiation, with loss- and gain-of-function mutants confirming its regulatory role in shoot branching architecture.
The study demonstrates that MYB‑bHLH‑WDR transcriptional complexes (MBW) are present in the liverwort Marchantia polymorpha, indicating that such complexes originated before the diversification of land plants. Functional analyses reveal that two MYB paralogs, MpMYB14 and MpMYB02, rely on a single bHLH partner (MpbHLH12) to regulate flavonoid biosynthesis and liverwort‑specific oil body maturation, suggesting an ancestral role in pigment production and a derived role in organelle development.
The study applied Spatial Analysis of Field Trials with Splines (SpATS) and Neighbor Genome-Wide Association Study (Neighbor GWAS) to barley field data, revealing that neighboring genotypes contribute to spatial variation in disease damage. Neighbor GWAS identified variants on chromosome 7H that modestly affect net form net blotch and scald resistance, suggesting that genotype mixtures could mitigate pest damage.