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The Golgi complex (GC) is the central station of the secretory pathway, through which several paths of intracellular transport are connected. The main function of the GC is glycosylation of proteins and lipids, and their subsequent sorting. The structure of the GC is extremely complicated, although in general it is unbelievably similar across different cells types and under different functional and pathological conditions. However, there are also a lot of differences between the GCs in different cells and under different normal and pathological conditions. Here, we compare the phenotypes of the GCs in different organisms under these different conditions, in particular according to morphological criteria. We propose a classification of the GC types that reflects the different features of the GC, and that depends on the different molecular machines. [ABSTRACT FROM AUTHOR]

Abstract: We did a comparative analysis of the small subunit ribosomal DNA (rDNA) for two species of Microsporidia, Semenovaia chironomi and Neoperezia chironomi, both parasites of Chironomus plumosus (Diptera, Chironomidae). These two microsporidial species have been described previously on the basis of light and electron microscopic studies. The former species is dimorphic, producing both single diplokaryotic spores and uninucleate spores in sporophorous vesicles (SPVs) in packets of 16, while the latter species is monomorphic, disporoblastic, producing only uninucleate spores in SPVs. Based on their life cycles, S. chironomi and N. chironomi were assigned to two different families, Burenellidae and Neopereziidae. However, molecular analysis shows 96.7% sequence similarity for the small subunit rDNA between these two species. Remarkable similarities of the spore ultrastructure (mainly of the extrusion apparatus) justify a transfer of S. chironomi to Neoperezia, establishing a new combination, Neoperezia semenovaiae. Neoperezia belongs to Clade V, Class Aquasporidia sensu , and is in its spore ultrastructure similar to its closest relatives, namely Bryonosema, Schroedera, Pseudonosema, Trichonosema and Janacekia. We therefore conclude that similarities in spore ultrastructure reflect the phylogenetic relatedness of these Microsporidia, as opposed to the strikingly diverse life cycles. [Copyright &y& Elsevier]

[Display omitted] Participation of molecular determinants of endocytosis in the processes of glomerular filtration and tubular reabsorption of albumin and lysozyme in the mesonephros of grass frogs (Rana temporaria L.), lake frogs (Rana ridibunda P.), and newts (Triturus vulgaris L.) is investigated. In all studied species, the constitutive expression of endocytic receptors in proximal tubule (PT) cells is established using immunofluorescence microscopy and immunoblotting. The certain stages of lysozyme and albumin endocytosis involving megalin/LRP2, cubilin, clathrin and protein Rab11 are detailed, and the central role of ligand-induced megalin/LRP2 activity in this process is shown. Increased ligand-induced expression for clathrin and Rab11was also found. In grass frogs, the different patterns of endocytic receptors and both absorbed proteins in the initial parts of proximal tubules suggest the proximo-distal specialization of absorptive processes along these tubule segments, similar to this in more complex mammalian nephrons. This data, as well as the revealed peculiarities of ligand-receptor interactions during intracellular trafficking of proteins prove that megalin is mainly involved in the absorption of lysozyme. At the same time, albumin absorption is mediated by both receptors, or cubilin contributes the most. The detection of endocytic receptor in glomerular structural elements in frogs and newts suggests the participation of filtration barrier components in endocytosis of filterable proteins. The results represent a new contribution to the study of the fundamental mechanisms of renal protein uptake in the amphibian mesonephros as a more primitive kidney compared to mammalian metanephros. [ABSTRACT FROM AUTHOR]