Selective Autophagy: Talking with the UPS

Far from now are the days when investigators raced to identify the proteolytic system responsible for the degradation of their favorite protein. Nowadays, it is well accepted that a given protein can be degraded by different systems depending on factors such as cell type, cellular conditions, or functionality of each proteolytic pathway. The realization of this sharing of substrates among pathways has also helped to unveil deeper levels of communication among the different proteolytic systems. Thus, cells often respond to blockage of one degradative mechanism by upregulating any of the other available pathways. In addition, effectors and regulators of one proteolytic system can be degraded by a different proteolytic pathway that exerts, in this way, a regulatory function. In this mini review, we describe the different levels of cross-talk among autophagic pathways and the ubiquitin/proteasome system. We also provide examples of how this proteolytic communication is used for compensatory purposes in different pathological conditions and discuss the possible therapeutic potential of targeting the modulators of the cross-talk among proteolytic pathways.     

The Cytotoxic and Proapoptotic Activities of Hypnophilin are Associated with Calcium Signaling in UACC‐62 Cells

Hypnophilin (HNP) is a sesquiterpene that is isolated from Lentinus cf. strigosus and has cytotoxic activities. Here, we studied the calcium signaling and cytotoxic effects of HNP in UACC‐62 cells, a human skin melanoma cell line. HNP was able to increase the intracellular calcium concentration in UACC‐62 cells, which was blocked in cells stimulated in Ca²⁺‐free media. HNP treatment with BAPTA‐AM, an intracellular Ca²⁺ chelator, caused an increase in calcium signals. HNP showed cytotoxicity against UACC‐62 cells in which it induced DNA fragmentation and morphological alterations, including changes in the nuclear chromatin profile and increased cytoplasmatic vacuolization, but it had no effect on the plasma membrane integrity. These data suggest that cytotoxicity in UACC‐62 cells, after treatment with HNP, is associated with Ca²⁺ influx. Together, these findings suggest that HNP is a relevant tool for the further investigation of new anticancer approaches. © 2013 Wiley Periodicals, Inc. J BiochemMol Toxicol 27:479‐485, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21507     

Frammenti cotiledonari di Aesculus hippocastanum L. coltivati in vitro. Primi dati sul comportamento dell'amido e dell'escina

Abstract

Fragments of Aesculus hippocastanum L. cotyledons grown in vitro. First results about starch and aescin characteristic features.—Cotyledon fragments of Aesculus hippocastanum grown in vitro in different media have been able to form callus and roots. The starch granules in the new cells are compound in structure and morphologically different from the simple cotyledon granules, whereas they are similar to the granules of the other parts of the plant in toto. Moreover, the callus has no aescin even though it originates from the cotyledor tissues.     

Osservazioni ecologiche preliminari su Petagnia saniculifolia Guss., raro endemismo siculo

Abstract

Preliminary ecological observations on Petagnia saniculifolia Guss., a rare sicilian endemism. — The Authors present the preliminary results of some observations on the anatomy and ecology of Petagnia saniculifolia Guss. and a synthetic phytosociological table in which some species of Molinio-Arrhenatheretea and Querco-Fagetea are present. The particular needs of this species and the precarious environmental conditions are pointed out.     

Response of greenhouse tomato to salt stress and K+ supplement

Abstract

The effect of NaCl salinity and potassium supplement on growth, tissue ion concentration, photosynthesis, yield and fruit quality characteristics of tomato plants was studied. Tomato plants, hyb. Belladonna, were grown in 8.5 l pots, filled with 1:3 sand:perlite mixture and irrigated with a half-strength Hoagland solution through a closed hydroponic system. Six irrigation treatments were applied, including combinations of 3 salinity (0, 35 and 70 mM NaCl) and two potassium levels (K1: 200 ppm and K2: 400 ppm) in the nutrient solution. Salinity reduced photosynthesis resulting in reduced plant height and dry weight. Yield was reduced by 25% and 69% at 35 and 70 mM, respectively, as compared to control plants (0 mM NaCl). Both total soluble solids and titratable acidity of the fruit increased with increasing salinity and K levels. The application of high potassium level (K2) reduced the concentration of Na and increased that of K in the leaves and roots of the plants, as compared to K1 treatment. Toxicity symptoms were mostly observed in the leaves of 70K1 plants, while no visual symptoms of toxicity were observed in 70K2 treatment. Despite the positive effects of potassium supplement in reducing Na concentration and the absence of toxicity symptoms in the leaves, plant growth was not improved, while leaf photosynthesis was reduced. Furthermore, no positive effects in the percentage of marketable fruit, mean fruit weight and yield were observed in the plants receiving extra K.     

Studio Del Ritmo Vegetativo Di Olea Europaea L. in Messina Negli Anni 1952–54

Summary

The vegetative growth of the olive tree in Messina is described. The growth period begins at the end of March and prosecutes without interruption as late as November. The secondary wood tissue producted during summer time (from Yuly to August) is abnormal being of a parenchimatoide type. During winter there is a well defined rest period.

The cambium produces secondary wood and bark with an alternate rythm, so that in spring the wood production prevails on the liber and in autumn the opposite condition is realized.

Each phase of production of secondary conducting tissues (wood as well as bark) is followed by a phase of starch storing.

In the stem several false wood rings are produced during one year, while in the young branches each wood ring corresponds to one year.

The longitudinal growth and cork formation on the branches of the year are particularly pronounced during spring (March-May).

Cambium cells swell in a characteristic way before they start dividing and collapse during the resting periods, thickening evidently their walls, so that in winter it is difficult to distinguish a cambial cell from a parenchimatic one.

The behaviour of the vegetative growth of the olive tree in Messina is discussed on the base of the climatic characters of the region.     

Appunti Sulla Flora Stradale E Ruderale Dei Dintor Ni Di Molfetta (Bari)

Summary

The author has studied the flora of a few country lanes in the surroundings of Molfetta (Apulia). The various stations are described and the plants collected are listed.     

Polyamines and RNA content in wheat embryos from seeds of different age

Abstract

The content of polyamines and RNA in isolated embryos from dry resting seeds of durum wheat has been determined. This, with the aim to investigate the variations of the polyamines and RNA amounts during the ageing process and to correlate them with the loss of germination capacity of the seeds. The results showed that the total polyamines increase while the RNA content decreases during the ageing of the embryos. Since no great difference exists as to the polyamine content between the embryos from seeds capable and incapable to germinate, it appears to be lacking a close relationship between the polyamine content and the germination capacity of the examined seeds. The decrease of the RNA content and the corresponding increase of the polyamine-N/RNA-nucleotide ratio, seem to suggest that the loss of germination capacity of the wheat seed could be related to impaired regulation properties during the ageing process.