We have examined the effect of gabaculine (3-amino-2,3-dihydrobenzoic acid) on chlorophyll (Chl) binding photosystem (PS) apoproteins in thylakoid ineinbranes relative to the effect on pigment accumulations and grana thylakoid stacking in wheat {Triticum aesíivum L.) seedling leaves. The accumulations of critical PSI, PS2, light- harvesting complex (LHCl and LHC2) apoproteins differed in response to gabaculine treatment. The reaction center proteins. Dl of PS2 and the 68 kDa PSI, were not detected in either primary or secondary leaf chloroplasts of treated etiolated seedlings after greening or secondaiy leaf chloroplasts of treated green seedlings. However, the LHC apoproteins accumulated at reduced levels relative to the Controls and LHCl was more sensitive to treatment than LHC2. Gabaculine decreased plastid pigment levels in primary leaf chloroplasts of treated etiolated seedlings by only 50 % and in secondaiy leaf chloroplasts by more than 85 % of that in the Controls. The accumulations of Chl o, Chl h, and the carotenoids, neoxanthin and í3-carotene, were most sensitive to treatment and were decreased in a similar manner. Granal thylakoid development was more sensitive to treatment than stroma thylakoid development and LHC2 apoprotein accumulations enriched stroma thylakoids in some treatments. The lack of starch and critical reaction center apoproteins in these chloroplasts suggest a loss of photosynthetic competency.
A new observation network has been built to observe the surface manifestations of undermining at Gabriela locality. This locality lies in the Czech part of the Upper Silesian Coal Basin and the history of the hard coal underground exploitation is more than 150 years long here. Recently, the last coal mining panel was started to be exploited here. Its location and mining parameters are very suitable for the analysis of the actual and future surface changes caused by undermining. The fixed points of the observation network are surveyed by geodetic GNSS me thod. This method enables the evaluation of both vertical subsidence and horizontal displacements. Such complex evalua tion of processes on the surface of the undermined territory makes it possible to understand the progress of the subsidence depression and to capture the final phase of the surface undermining changes, i.e. the phase of the subsidence decline., Vlastimil Kajzar, Hana Doležalová, Kamil Souček and Lubomír Staš., and Obsahuje bibliografické odkazy
Gain-of-function (GOF) mutations in ion channels are rare events, which lead to increased agonist sensitivity or altered gating properties, and may render the channel constitutively active. Uncovering and following characterization of such mutants contribute substantially to the understanding of the molecular basis of ion channel functioning. Here we give an overview of some GOF mutants in polymodal ion channels specifically involved in transduction of painful stimuli - TRPV1 and TRPA1, which are scrutinized by scientists due to their important role in development of some pathological pain states. Remarkably, a substitution of single amino acid in the S4-S5 region of TRPA1 (N855S) has been recently associat ed with familial episodic pain syndrome. This mutation increases chemical sensitivity of TRPA1, but leaves the voltage sensitivit y unchanged. On the other hand, mutations in the analogous regi on of TRPV1 (R557K and G563S) severely affect all aspects of channel activation and lead to spontaneous activity. Comparison of the effects induced by mutations in homologous positions in different TRP receptors (or more generally in other distan tly related ion channels) may elucidate the gating mechanisms conserved during evolution., S. Boukalova ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy