The F-actin cytoskeleton in syncytia from non-clonal progenitor cells

The actin cytoskeleton of plant syncytia (a multinucleate cell arising through fusion) is poorly known: to date, there have only been reports about F-actin organization in plant syncytia induced by parasitic nematodes. To broaden knowledge regarding this issue, we analyzed F-actin organization in special heterokaryotic Utricularia syncytia, which arise from maternal sporophytic tissues and endosperm haustoria. In contrast to plant syncytia induced by parasitic nematodes, the syncytia of Utricularia have an extensive F-actin network. Abundant F-actin cytoskeleton occurs both in the region where cell walls are digested and the protoplast of nutritive tissue cells fuse with the syncytium and also near a giant amoeboid in the shape nuclei in the central part of the syncytium. An explanation for the presence of an extensive F-actin network and especially F-actin bundles in the syncytia is probably that it is involved in the movement of nuclei and other organelles and also the transport of nutrients in these physiological activity organs which are necessary for the development of embryos in these unique carnivorous plants. We observed that in Utricularia nutritive tissue cells, actin forms a randomly arranged network of F-actin, and later in syncytium, two patterns of F-actin were observed, one characteristic for nutritive cells and second—actin bundles—characteristic for haustoria and suspensors, thus syncytia inherit their F-actin patterns from their progenitors

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Not AvailableCastor being a perennial, cross-pollinated, sexually polymorphic crop with high environmental sensitivity, initial plant breeding efforts were restricted to plant height and duration. Domestication of a wild, perennial crop to an annual crop of medium plant height and duration is the first success. Further, development of a two-line breeding system and standard seed production technology led to successful commercial exploitation of heterosis. Being a monotypic genus, diversification of parental base is restricted to intra-generic, intraspecific, or inter-varietal hybridization. Phenotypic expression is highly plastic and varies with locations and seasons. Majority of the morphological characters are monogenic, independently assorted with very limited linkages among the traits. However, information on genetics of major morphological characters is scattered in several old publications. Conventional breeding methods were successful in developing about 40 high-yielding hybrids and varieties with inbuilt resistance to major pests and diseases. An effort is made in the present chapter to consolidate the information on genetics and breeding methods followed in India and elsewhere.Not Availabl

Heteromeric Solute Carriers: Function, Structure, Pathology and Pharmacology

Solute carriers form one of three major superfamilies of membrane transporters in humans, and include uniporters, exchangers and symporters. Following several decades of molecular characterisation, multiple solute carriers that form obligatory heteromers with unrelated subunits are emerging as a distinctive principle of membrane transporter assembly. Here we comprehensively review experimentally established heteromeric solute carriers: SLC3-SLC7 amino acid exchangers, SLC16 monocarboxylate/H+ symporters and basigin/embigin, SLC4A1 (AE1) and glycophorin A exchanger, SLC51 heteromer Ost α-Ost β uniporter, and SLC6 heteromeric symporters. The review covers the history of the heteromer discovery, transporter physiology, structure, disease associations and pharmacology - all with a focus on the heteromeric assembly. The cellular locations, requirements for complex formation, and the functional role of dimerization are extensively detailed, including analysis of the first complete heteromer structures, the SLC7-SLC3 family transporters LAT1-4F2hc, b0,+AT-rBAT and the SLC6 family heteromer B0AT1-ACE2. We present a systematic analysis of the structural and functional aspects of heteromeric solute carriers and conclude with common principles of their functional roles and structural architecture