Partial disruption of the larger particles into smaller particles during detergent solubilization. It should be noted that this is the first time that a member of the cation-chloride cotransporter family is purified, and that its shape, dimensions, low-resolution structure and oligomeric state is determined by TEM. In a variety of eukaryotic organisms, a family of serine/ threonine protein kinases known as the mitogen-activated protein kinases play critical roles in the transduction of a variety of extracellular signals and regulation of various development and differentiation processes. The MAPK cascades are conserved in eukaryotes and have been studied extensively in many organisms. In filamentous fungi, MAPKs mainly fall into three subgroups represented by Fus3/Kss1, Slt2, and Hog1 of Saccharomyces cerevisiae. The Fus3/Kss1 homolog is more extensively studied than the other two MAPKs in fungal pathogens. In the rice blast fungus Magnaporthe oryzae, the PMK1 MAP kinase gene is essential for appressorium formation and invasive growth. In the wheat scab fungus Fusarium graminearum, the map1 deletion mutants are female sterile, non-pathogenic, and reduced in conidiation and infectious growth. In Ustilago maydis, Kpp2 and Kpp6 are two Fus3/Kss1 MAPKs with overlapping functions in mating and plant infection. The ubc3/kpp2 mutant is defective in HhAntag691 pheromone responses and the formation of filamentous dikaryons and reduced in virulence. In contrast, Kpp6 plays a more critical role in appressorial penetration than Kpp2. The kpp6 mutant is reduced in virulence and defective in the penetration of plant cuticle. The kpp2 kpp6 double mutants are abolished in mating and nonpathogenic on maize plants. The Fus3/Kss1 homologs also have been functionally characterized in several human pathogens. In Candida albicans, the Cek1 MAPK plays a critical role in pathogenesis. In Cryptococcus neoformans, the CPK1 MAPK pathway is important for mating and haploid fruiting but dispensable for virulence. Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most important diseases of wheat worldwide. Pst is an obligate biotrophic fungus belonging to the Uredinales. The major phase of the stripe rust life cycle is urediniospores, which can germinate in water but germ tubes will die without host cells. After successful adhesion to the wheat leaves, urediniospores produce germ tubes, which elongate along leaf veins until they encounter stomatal opening. After entering the substomatal space in wheat leaves, the fungus starts to successively differentiate other infection structures, e.g., substomatal vesicles, infection hypha, haustorial mother cell, and eventually haustoria, a structure to withdraw nutrients from host cells. The majority of germ tubes penetrates stomata after 12 hours of germination, and formation of haustorial mother cells increases rapidly after 18 hours of inoculation.