Plant hormones are master regulators of plant growth and development. Better knowledge of their spatial signaling and homeostasis (transport and metabolism) on the lowest structural levels (cellular and subcellular) is therefore crucial to a better understanding of developmental processes in plants. Recent progress in phytohormone analysis at the cellular and subcellular levels has greatly improved the effectiveness of isolation protocols and the sensitivity of analytical methods. This review is mainly focused on homeostasis of two plant hormone groups, auxins and cytokinins. It will summarize and discuss their tissue- and cell-type specific distributions at the cellular and subcellular levels.

• Klíčová slova
• auxin, cellular level, cytokinin, phytohormone metabolism, phytohormone transport, subcellular level,
• MeSH
• biologický transport MeSH
• cytokininy metabolismus   MeSH
• fyziologie rostlin * MeSH
• homeostáza * MeSH
• intracelulární prostor metabolismus   MeSH
• kyseliny indoloctové metabolismus   MeSH
• metabolické sítě a dráhy MeSH
• organely metabolismus   MeSH
• regulátory růstu rostlin metabolismus   MeSH
• rostlinné buňky metabolismus   MeSH
• vývoj rostlin * MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• cytokininy MeSH
• kyseliny indoloctové MeSH
• regulátory růstu rostlin MeSH

Histidine-containing phosphotransfer proteins from Arabidopsis thaliana (AHP1-5) act as intermediates between sensor histidine kinases and response regulators in a signalling system called multi-step phosphorelay (MSP). AHP proteins mediate and potentially integrate various MSP-based signalling pathways (e.g. cytokinin or osmosensing). However, structural information about AHP proteins and their importance in MSP signalling is still lacking. To obtain a deeper insight into the structural basis of AHP-mediated signal transduction, the three-dimensional structure of AHP2 was determined. The AHP2 coding sequence was cloned into pRSET B expression vector, enabling production of AHP2 fused to an N-terminal His tag. AHP2 was expressed in soluble form in Escherichia coli strain BL21 (DE3) pLysS and then purified to homogeneity using metal chelate affinity chromatography and anion-exchange chromatography under reducing conditions. Successful crystallization in a buffer which was optimized for thermal stability yielded crystals that diffracted to 2.5 Å resolution.

• Klíčová slova
• AHP2, Arabidopsis thaliana, histidine phosphotransfer proteins, multi-step phosphorelay,
• MeSH
• Arabidopsis metabolismus   MeSH
• difrakce rentgenového záření MeSH
• elektroforéza v polyakrylamidovém gelu MeSH
• fosfotransferasy chemie   izolace a purifikace   MeSH
• krystalizace MeSH
• proteiny huseníčku chemie   izolace a purifikace   MeSH
• signální transdukce * MeSH
• tranzitní teplota MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• AHP2 protein, Arabidopsis MeSH Prohlížeč
• fosfotransferasy MeSH
• proteiny huseníčku MeSH