SALT OVERLY SENSITIVE 4 (SOS4); FUNCTIONS IN: pyridoxal kinase activity, kinase activity; INVOLVED IN: pyridoxine biosynthetic process, hyperosmotic salinity response, trichoblast differentiation, pyridoxal 5'-phosphate salvage; LOCATED IN: chloroplast; EXPRESSED IN: 23 plant structures; EXPRESSED DURING: 14 growth stages; CONTAINS InterPro DOMAIN/s: Pyridoxal phosphate (active vitamin B6) biosynthesis, pyridoxal kinase (InterPro:IPR004625), Phosphomethylpyrimidine kinase type-1 (InterPro:IPR013749); BEST Arabidopsis thaliana protein match is: thiamin biosynthesis protein, putative (TAIR:AT1G22940.1); Has 6182 Blast hits to 6179 proteins in 1931 species: Archae - 81; Bacteria - 5137; Metazoa - 195; Fungi - 190; Plants - 75; Viruses - 0; Other Eukaryotes - 504 (source: NCBI BLink). AT5G37850 SOS4 SALT OVERLY SENSITIVE 4 ATSOS4