SFB 1664: Plant Proteoform Diversity - SNP2Prot (Projects A04, C04, D01)

A04 investigates the interaction of protein complexes regulating meiotic recombination, focusing on REC8-cohesin complexes in barley. REC8.2, one of two copies in cereal genomes, influences recombination rate variation. Using wild barley lines, this project examines the impact of allelic variation on recombination frequencies through cytological and biochemical/biophysical methods, including cryo-EM. The aim is the elucidation of binding specificities within the REC8-cohesin complex and how these are affected by different proteoforms.

C04 focuses on MEVALONATE KINASE (MVK) in the mevalonate pathway crucial for isoprenoid biosynthesis. Several climate factors are associated with diverse MVK alleles. Mapping nsSNPs onto the 3-D structure suggests surface localization, influencing potential dimerization. Heterologous expression, purification, and cryo-EM-based modelling of proteoforms will reveal biochemical alterations. Differing MVK activities in accessions or haplotypes will be phenotypically analysed under varied environmental conditions, advancing understanding of MEV pathway regulation for metabolic engineering of terpenoids.

D01 aims to computationally model Arabidopsis proteoforms on a proteome-wide scale. Given the limited protein structures for Arabidopsis, the project will connect genomic information from SNPstar with protein structure and function predictions. This initiative will establish a crucial structural bioinformatics resource, creating a comprehensive atlas of nsSNP effects in Arabidopsis. This resource will facilitate investigations into the links between genetic variation and phenotypic outcomes, benefiting multiple CRC projects. Additionally, it lays the foundation for enhancing plant proteins in subsequent funding periods.