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Muscle LIM protein (MLP) is a microtubule-associated protein expressed in cardiac and muscle tissues that belongs to the cysteine-rich protein (CSRP/CRP) family. MLP has a central role during muscle development and for architectural maintenance of muscle cells. However, muscle cells rely on autophagy during differentiation and for structural maintenance. To study the role of MLP in autophagy, we have used C2C12 mouse myoblasts silenced or overexpressing MLP. Our results show that MLP contributes to the correct autophagosome formation and flux by interacting with LC3 as demonstrated by co-immunoprecipitation and PLA assay. In fact, MLP silencing results in decreased LC3-II staining and absent degradation of long-lived proteins. Moreover, MLP silencing impaired myoblasts differentiation as measured by decreased expression of MyoD1, MyoG1 and myosin heavy chain. Ultrastructural analysis revealed the presence of large empty autophagosomes in myoblasts and multimembranous structures in myotubes from MLP-silenced clones. Impaired autophagy in MLP-silenced cells resulted in increased susceptibility to apoptotic cell death. In fact, treatment of MLP-silenced C2C12 myoblasts and myotubes with staurosporine resulted in increased caspase-3 and PARP cleavage as well as increased percentage of cell death. In conclusion, we propose that MLP regulates autophagy during muscle cell differentiation or maintenance through a mechanism involving MLP/LC3-II interaction and correct autophagosome formation.

Rice (Oryza sativa L.) is the primary staple food source for more than half of the world’s population. In many developing countries, increased use of fertilizers is a response to increase demand for rice. In this study, we investigated the effects of three principal fertilizer components (nitrogen, phosphorus and potassium) on the development of potted rice plants and their effects on fitness traits of the brown planthopper (BPH) [Nilaparvata lugens (Stål) (Homoptera: Delphacidae)], which is a major pest of rice in Bangladesh and elsewhere. Compared to low fertilizer inputs, high fertilizer treatments induced plant growth but also favored BPH development. The BPH had higher survival, developed faster, and the intrinsic rate of natural increase (r m) was higher on well-fertilized than under-fertilized plants. Among the fertilizer inputs, nitrogen had the strongest effect on the fitness traits of BPH. Furthermore, both the “Plant vigor hypothesis” and the “Plant stress hypothesis” were supported by the results, the former hypothesis more so than the latter. These hypotheses suggest that the most suitable/attractive hosts for insect herbivores are the most vigorous plants. Our findings emphasized that an exclusive focus on yield increases through only enhanced crop fertilization may have unforeseen, indirect, effects on crop susceptibility to pests, such as BPH.

The beneficial effects of the Mediterranean diet (MD) had been first observed about 50 years ago. Consumption of fresh vegetables and fruits, cereals, red wine, nuts, legumes, etc. has been regarded as the primary factor for protection from many human pathologies by the Mediterranean diet. Subsequently, this was attributed to the presence of polyphenols and their derivatives that, by exerting an anti-inflammatory and anti-oxidative effect, can be involved in the prevention of many diseases. Clinical trials, observational studies and meta-analysis have demonstrated an antiageing effect of MD accompanied by a reduced risk of age-related pathologies, such as cardiovascular, metabolic and neurodegenerative diseases, as well as cancer. The scientific explanation of such beneficial effects was limited to the reduction of the oxidative stress by compounds present in the MD. However, recently, this view is changing thanks to new studies aimed to uncover the molecular mechanism(s) activated by components of this diet. In particular, a new class of proteins called sirtuins have gained the attention of the scientific community because of their antiageing effects, their ability to protect from cardiovascular, metabolic, neurodegenerative diseases, cancer and to extend lifespan in lower organisms as well as in mammals. Interestingly, resveratrol a polyphenol present in grapes, nuts and berries has been shown to activate sirtuins and such activation is able to explain most of the beneficial effects of the MD. In this review, we will highlight the importance of MD with particular attention to the possible molecular pathways that have been shown to be influenced by it. We will describe the state of the art leading to demonstrate the important role of sirtuins as principal intracellular mediators of the beneficial effects of the MD. Finally, we will also introduce how Mediterranean diet may influence microbioma composition and stem cells function.

The ongoing molecular investigation of the basic contractile units of the sarcomere in striated muscles have revealed a highly complex system composed of a large number of proteins each one with a specific task.1 However, a growing number of studies is pointing the attention to the fact that many of these structural proteins may also be involved in pathways and functions other than contraction but always related to muscle cell maintenance, repair, differentiation, signaling, etc.1 In this context an important role has been attributed to the muscle LIM protein (MLP). MLP is a member of the cysteine and glycine rich protein (CSRP) family that is composed by CSRP1, CSRP2 and CSRP3 or MLP. CSPRs, in turn, belong to the larger family of LIM domain proteins.2 MLP is expressed in striated muscle at the level of sarcomere, the intercalated disk and the costamere where it interacts with telethonin, α-actinin, cofilin-2 and calcineurin among others and contains two LIM domains that are zinc finger domains composed of~55 aminoacids with 8 highly conserved residues, mostly cysteine and histidine that are located at defined intervals.2 Through the LIM domain, MLP can modulate protein interaction and formation of macromolecular structures. Another peculiarity of MLP is that it can shuttle from the cytosol to the nucleus where it serves as a scaffold protein to adapt transcription factors to their DNA-binding sequences. 2,3 In fact, MLP is involved myocyte differentiation by activating transcription factors such as MyoD, myogenin, etc. 4 To this effect, mutations in the N-terminal region of MLP have been linked to the development of dilated cardiomyopathy (DCM) or hypertrophic cardiomyopathy (HCM). Moreover, MLP protein levels or intracellular localization are altered in skeletal myopathies, such as fascioscapulohumeral muscular dystrophy, nemaline myopathy and limb girdle muscular dystrophy type 2B. 5,6 Therefore, the current dogma foresee an important role for MLPin the maintenance of muscle cytoarchitecture as well as in the differentiation of muscle cells. However, the cellular and molecular mechanism(s) through which MLP carries out its function is (are) still obscure.Using a myoblast cell line we have recently demonstrated that MLP uses macroautophagy to control differentiation of myobalsts into myotubes as well as survival of myotubes in the presence of a cell death stimulus. 7In particular, we have used MLP silenced myoblasts to show an impairment of autophagy that, in turn, results in decreasedmyotubes formation and decreased resistance to cell death. However, the question was: how can MLP control autophagy? We provided evidences that MLP interacts and associates with LC3, a widely used autophagy marker with a crucial role during autophagosome formation. Interestingly both MLP and LC3 are microtubule associated proteins. Therefore, besides controlling muscle cell differentiation by modulating the expression of MyoD1 and myogenin mRNA, we also show that cytosolic MLP is important for the correct assembly and flux of...

The experiment was conducted in the Laboratory, Department of Plant Pathology,  HSTU, Dinajpur during April – July 2010 to know the effect of abiotic and biotic  factors, storage periods and storage containers on the seed quality of French  bean. Tin container showed the highest germination, normal seedlings and  vigour index which were followed by polythene bag, where Gunny bag showed  the lowest germination, normal seedlings and vigour index upto 60 days after  storage. The highest 1000-seed weight, moisture content, abnormal seedlings,  seed rot and incidence of the Fusarium oxysporum were recorded in Gunny bag,  where the lowest of these parameters were recorded in Tin container. Seed  colour of Tin container were more or less same as initial colour, but seeds of  Gunny bag were changed into fade or brown colour at 60 days after storage.  Moisture content, 1000-seed weight, abnormal seedlings, seed rot, fungi  association were increased, but germination and normal seedlings were  decreased with the increase of storage periods. Among the three containers, Tin  container was the best and the Gunny bag was the worst storage containers upto  60 days of storage for French bean seed. DOI: http://dx.doi.org/10.3329/bjar.v37i2.11221 Bangladesh J. Agril. Res. 37(2): 195-205, June 2012

Fruits and vegetables are important sources of nutrients for mankind. Among the various fruits available in Bangladesh, mango occupies a vital place in the human nutrition for its delicious taste and higher nutritious value. In this study, five mango varieties, viz. Fazli, Amrupali, Langra, Gopalbogh and Misribogh, were tested to evaluate the quality of these mango varieties available in Northern Bangladesh. Physiochemical characteristics, including moisture, ash, total carbohydrates, total solids, total soluble solids (TSS), pH, acidity, total sugars and ascorbic acid contents were evaluated. The results showed that there were significant (p< 0.05) differences among mangoes of all varieties for physicochemical parameters. In case of proximate composition, the mango variety Amrupali showed the highest ash content (2.34±0.15) and fat content (1.18±0.13). Protein content (0.94±0.12) and total fiber (2.67%) content was shown to be the highest by Gopalbogh and Misribogh, respectively. The selected mango varieties contained TSS of 12.87~20.55oBrix, pH of 4.45~4.67, titrable acidity of 0.07~0.42%, reducing sugar of 8.40~15.43%, non-reducing sugar of 9.24~10.48%, and total sugarof 18.88~25.12%. The study findings would be helpful for the consumers, dietitian and industry policymakers.

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