Finally, the performance of transgenic Arabidopsis plants overexpressing AtVIP1, a gene encoding a bZIP transcription factor protein, was investigated. Our results demonstrated that AGB1 interacts with AtMPK6 and may negatively regulate the ABA signaling pathway and drought tolerance by down-regulating the AtMPK6, AtVIP1, and AtMYB44 cascade in Arabidopsis. Accurate DNA segregation to progeny cells is fundamental to the survival of organisms and continuity of life. In Prokaryotes, pioneering studies on the segregation of low-copy-number plasmids have revealed the existence of partitioning systems ensuring active distribution of DNA molecules to daughter cells and thus their stable inheritance in bacterial populations. The great majority of plasmidic par systems comprise three components: an NTPase that forms a dynamic scaffold for plasmid movement, specific DNA-binding protein, and a cis-acting centromere-like sequence recognized and bound by B-component, all together forming a ��minimalist�� DNA segregation machine. Bacterial TWS119 genomics has revealed the presence of an operon encoding homologs of type IA plasmidic Par proteins in close proximity of the origin of replication, oriC, in the vast majority of bacteria with the exception of two families of ��- proteobacteria, Enterobacteriaceae and Pasteurellaceae and one family of Mollicutes, Mycoplasmataceae. The GDC-0941 highly-conserved multiple copies of parS, the cis-acting centromere-like sequence, are mainly localized in the ori domain comprising 20% of the genome around oriC, although in some species, e.g., Bacillus subtilis and Pseudomonas aeruginosa, additional parS sequences are dispersed outside the ori domain. The hydrolytic activity of ParA, P-loop ATPase with a deviant Walker A motif, provides energy and orchestrates the movement of the nucleoprotein complex of ParB bound to its cognate parS site. The chromosomal partitioning systems participate in the chromosome segregation by orienting the ori domain spatially, directing the newly replicated origins to the cell poles, compacting the chromosome by creating a platform for SMC loading, and holding the ori domains at the poles until completion of cell division. Numerous studies on various bacterial species have revealed on one hand the highly conserved nature of the partitioning components, and on the other the participation of parABS systems not only in chromosome segregation but also in other vital cell processes in a species-specific manner. The parABS systems may be involved in the regulation of replication, initiation of sporulation, septation and DNA translocation as well as growth control and cytokinesis or motility. Transcriptomic analyses of par mutants have demonstrated the role of Par proteins as global transcriptional regulators in P. aeruginosa and Vibrio cholerae. The interactions of ParA and ParB homologues with one another and with other proteins have been studied thoroughly. The interactions of chromosomal ParBs with the centromere-like sequences have been also analyzed, demonstrating their ability to specifically bind parS, spread on DNA, form nucleoprotein complexes and transcriptionally silence genes adjacent to parS. Less is known about why there are multiple parS sites on the chromosome and the roles they play. The binding site for chromosomal ParB, first identified for Spo0J in B. subtilis as the 16-nucleotide sequence tGTTtCAcGTGAAAAa/g, seems to be highly conserved in the primary chromosomes throughout the bacterial kingdom. The secondary chromosomes of multipartite bacterial genomes possess their own parABS systems demonstrating intra- as well as inter-species structural and functional diversity.