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791.
792.
Diógenes Infante Sandy Molina Jhonny R. Demey Elizabeth Gámez 《Plant Molecular Biology Reporter》2006,24(2):205-217
Agaves are succulent monocot plants rich in fibers, sugars and other important compounds. They are also valued as ornamental
plants and for their ability to grow in poor soils. In the present study, inverse sequence-tagged repeats (ISTR) and amplified
fragment length polymorphism (AFLP) analysis were used to study genetic diversity in differentAgavaceae plant samples. Comparison of the banding patterns between the mother plant and rhizome-derived daughter plants showed that
genetic variability is generated during asexual reproduction in these species. Phylogenetic relationships amongAgave species were obtained using unweighted pair-group method, arithmetic average (UPGMA) analysis. Genetic diversity through
asexual propagation allows for genetic selection and improvement within these asexually propagated plants. 相似文献
793.
Differential effects of phorbol ester (PMA) on blocker-sensitive ENaCs of frog skin and A6 epithelia
Els Willem J.; Liu Xuehong; Helman Sandy I. 《American journal of physiology. Cell physiology》1998,275(1):C120
Activation ofprotein kinase C with phorbol 12-myristate 13-acetate (PMA) causedcomplex transient perturbations of amiloride-sensitive short-circuitNa+ currents(INa) in A6epithelia and frog skins that were tissue and concentration dependent.A noninvasive channel blocker pulse method of noise analysis (18) wasused to investigate how PMA caused time-dependent changes of apicalmembrane epithelial Na+ channel(ENaC) single-channel currents, channel open probabilities (Po), andchannel densities(NT). In A6epithelia, 5 and 50 nM PMA caused within 7 min concentration-dependentsustained decreases ofPo (~55% belowcontrol, 50 nM) and rapid compensatory transient increases ofNT within 7 min(~220% above control, 50 nM), resulting in either small transientincreases of INaat 5 nM PMA or small biphasic decreases ofINa at 50 nM PMA.In contrast to A6 epithelia, 50 and 500 nM PMA in frog skin causedafter a delay of at least 10 min transient increases ofNT to~60-70% above control at 30-60 min. Unlike A6 epithelia,Po was increased~15% above control within 7 min and remained within±10-15% of control for the duration of the 2-h experiments.Despite differences in the time courses of secondary inhibition oftransport in A6 epithelia and frog skin, the delayed downregulation oftransport was due to time-dependent decreases ofNT from theirpreelevated levels in both tissues. WhereasPo is decreasedwithin minutes in A6 epithelia as measured by noise analysis or bypatch clamp (8), the discrepancy in regulation ofNT in A6epithelia as measured by noise analysis and patch clamp is most likelyexplained by the inability of on-cell patches formed before treatmentof tissues with PMA to respond to regulation of their channeldensities. 相似文献