Analysis of the Function of Matrix Attachment Region-Binding Filament-Like Protein 1 (MFP1) in the Chloroplast Thylakoid Membrane of Arabidopsis Thaliana

Matrix Attachment Region-Binding Filament-Like Protein 1 (MFP1) is a DNA-binding long coiled-coil plant protein with a structure similar to that of the golgins of the Golgi apparatus, which aid in maintaining the organelle’s characteristic membrane stacks. Due to the similarities in the protein structure of MFP1 and golgins, and the similarities in structure between the Golgi apparatus and the thylakoid membrane, we hypothesized that MFP1 had a function like that of the golgins: facilitating the formation of the thylakoid grana stacks. Under ideal lighting conditions, the mutants did not appear any different from the wild-type, but when exposed to differing light conditions, the phenotype was expressed in the form of slower growth and a denser, slightly larger rosette. Experimental results suggest that MFP1 may play a role in photosynthetic adaptation, either in state transitioning (movement of LHCII to Photosystem I) or in adjusting the photosystem stoichiometry (changing the ratio of Photosystem I to Photosystem II).