Leaf traits associated with flavonol glycoside genes in soybean

In the soybean (Glycine max (L.) Merr.), the gene combination Fg1 Fg3 is responsible for the glycosylation in the biosynthesis of kaempferol triglucoside (K9) in leaves. The presence of K9 is associated with reduction in chlorophyll content, specific leaf mass, photosynthetic rate and stomatal frequency. Blocking the action of Fg1 Fg3 with the magenta flower gene wm prevents formation of K9 and restores leaf traits to normal. A direct effect of K9 on leaf development is postulated.     

Ligand-dependent differences in estrogen receptor beta-interacting proteins identified in lung adenocarcinoma cells corresponds to estrogenic responses

Background

A recent epidemiological study demonstrated a reduced risk of lung cancer mortality in breast cancer patients using antiestrogens. These and other data implicate a role for estrogens in lung cancer, particularly nonsmall cell lung cancer (NSCLC). Approximately 61% of human NSCLC tumors express nuclear estrogen receptor β (ERβ); however, the role of ERβ and estrogens in NSCLC is likely to be multifactorial. Here we tested the hypothesis that proteins interacting with ERβ in human lung adenocarcinoma cells that respond proliferatively to estradiol (E₂) are distinct from those in non-E₂-responsive cells.

Methods

FLAG affinity purification of FLAG-ERβ-interacting proteins was used to isolate ERβ-interacting proteins in whole cell extracts from E₂ proliferative H1793 and non-E₂-proliferative A549 lung adenocarcinoma cell lines. Following trypsin digestion, proteins were identified using liquid chromatography electrospray ionization tandem mass spectrometry (LC-MS/MS). Proteomic data were analyzed using Ingenuity Pathway Analysis. Select results were confirmed by coimmunoprecipitation.

Results

LC-MS/MS identified 27 non-redundant ERβ-interacting proteins. ERβ-interacting proteins included hsp70, hsp60, vimentin, histones and calmodulin. Ingenuity Pathway Analysis of the ERβ-interacting proteins revealed differences in molecular and functional networks between H1793 and A549 lung adenocarcinoma cells. Coimmunoprecipitation experiments in these and other lung adenocarcinoma cells confirmed that ERβ and EGFR interact in a gender-dependent manner and in response to E₂ or EGF. BRCA1 interacted with ERβ in A549 cell lines and in human lung adenocarcinoma tumors, but not normal lung tissue.

Conclusion

Our results identify specific differences in ERβ-interacting proteins in lung adenocarcinoma cells corresponding to ligand-dependent differences in estrogenic responses.

     

Deep brain stimulation: eye movements reveal anomalous effects of electrode placement and stimulation

One of the major difficulties in evaluating the efficacy of deep brain stimulation (DBS), or understanding its mechanism, is the need to distinguish the effects of stimulation itself from those of the lesion inevitably created during surgery. Recent work has shown that DBS of the subthalamic nucleus in Parkinson's disease greatly reduces the time it takes the eyes to make a saccade in response to a visual stimulus. Since this saccadic latency can be rapidly and objectively measured, we used it to compare the effects of surgery and of stimulation. We used a saccadometer to measure the saccadic latencies of 9 DBS patients (1) preoperatively, (2) the day after insertion of subthalamic nucleus electrodes, (3) three weeks later, prior to turning on the stimulator, and (4) after commencement of stimulation. Patients were on their anti-Parkinsonian medication throughout the study. It revealed an entirely unexpected and puzzling finding. As in previous studies an amelioration of symptoms is seen immediately after surgery, and then a further improvement when finally the stimulator is turned on, but in the case of saccadic latency the pattern is different: surgery produces a transient increase in latency, returning to baseline within three weeks, while subsequent stimulation reduced latency. Thus the differential effects of electrode placement and stimulation are completely different for saccades and for more general motor symptoms. This important finding rules out some over-simple interpretations of the mechanism of DBS, and needs to be taken into account in future attempts at modelling the neurophysiology of DBS.     

The role of fish-poultry integration on fish growth performance,yields and economic benefits among smallholder farmers in sub-Saharan Africa,Tanzania

Aquaculture practices from sub-Saharan Africa are characterised by low production, owing to improper technology. Production can be increased through integrating fish farming with other existing on-farm activities, particularly livestock husbandry. We assessed the role of fish-poultry integration on all male Nile tilapia, Oreochromis niloticus growth performance, yields and economic benefits among smallholder farmers in sub-Saharan Africa, Tanzania. The study also compared phytoplankton species composition, abundance and biomass between the fish-poultry integration and non-integrated system. After 180 days of the experiment, all male O. niloticus cultured under fish-poultry integration exhibited significantly higher growth rates than those in the non-integrated system (p < 0.05). Gross fish yield (GFY), net fish yield (NFY) and net annual yields (NAY) obtained from fish-poultry integration were significantly higher than those from non-integrated system (p < 0.05). Partial enterprise budget analysis revealed that fish-poultry integration was more profitable than the non-integrated system. Moreover, fish-poultry integrated system produced significantly higher phytoplankton abundance and biomass than those from the non-integrated system. Results demonstrate that rural smallholder farmers can achieve higher growth rate, farm net yields and income by integrating all male O. niloticus with other on-farm activities than practising a stand-alone fish culture system.     

Effects of double ligation of Stensen's duct on the rabbit parotid gland

Salivary gland duct ligation is an alternative to gland excision for treating sialorrhea or reducing salivary gland size prior to tumor excision. Duct ligation also is used as an approach to study salivary gland aging, regeneration, radiotherapy, sialolithiasis and sialadenitis. Reports conflict about the contribution of each salivary cell population to gland size reduction after ductal ligation. Certain cell populations, especially acini, reportedly undergo atrophy, apoptosis and proliferation during reduction of gland size. Acini also have been reported to de-differentiate into ducts. These contradictory results have been attributed to different animal or salivary gland models, or to methods of ligation. We report here a bilateral double ligature technique for rabbit parotid glands with histologic observations at 1, 7, 14, 30, 60 days after ligation. A large battery of special stains and immunohistochemical procedures was employed to define the cell populations. Four stages with overlapping features were observed that led to progressive shutdown of gland activities: 1) marked atrophy of the acinar cells occurred by 14 days, 2) response to and removal of the secretory material trapped in the acinar and ductal lumens mainly between 30 and 60 days, 3) reduction in the number of parenchymal (mostly acinar) cells by apoptosis that occurred mainly between 14–30 days, and 4) maintenance of steady-state at 60 days with a low rate of fluid, protein, and glycoprotein secretion, which greatly decreased the number of leukocytes engaged in the removal of the luminal contents. The main post- ligation characteristics were dilation of ductal and acinar lumens, massive transient infiltration of mostly heterophils (rabbit polymorphonuclear leukocytes), acinar atrophy, and apoptosis of both acinar and ductal cells. Proliferation was uncommon except in the larger ducts. By 30 days, the distribution of myoepithelial cells had spread from exclusively investing the intercalated ducts pre-ligation to surrounding a majority of the residual duct-like structures, many of which clearly were atrophic acini. Thus, both atrophy and apoptosis made major contributions to the post-ligation reduction in gland size. Structures also occurred with both ductal and acinar markers that suggested acini differentiating into ducts. Overall, the reaction to duct ligation proceeded at a considerably slower pace in the rabbit parotid glands than has been reported for the salivary glands of the rat.     

Integrins mediate a neuronal survival signal for oligodendrocytes.

Target-dependent survival of newly differentiated cells is an important part of neural development. In the case of myelin-forming oligodendrocytes, it matches the number of oligodendrocytes to the available axons [1]. In addition to growth factors, an axonal signal regulates this survival: when axons are transected, oligodendrocytes die and, conversely, when the number of axons is increased by genetic manipulation, oligodendrocyte numbers increase [2] [3]. Newly formed oligodendrocytes that fail to contact axons undergo apoptosis, and co-culture experiments that model axon-glial interactions in vitro reveal a neuronal survival effect not present in neuron-conditioned medium [4] [5], suggesting that the signal is non-diffusible and present on the surface of axons. The nature of these neuronal signals is unknown, as are the mechanisms by which they interact with growth-factor-mediated survival signals. As integrins can regulate survival in other cell types [6] [7] [8], we determined whether integrins are involved in the neuronal survival effect. We found that the laminin receptor alpha6beta1 integrin, which is expressed on oligodendrocytes, enhances the sensitivity of oligodendrocytes to the survival effect of growth factors. On the basis of this interaction between integrin and growth-factor-mediated signalling, we propose a simple model by which signals from axons and other cell types might interact to regulate oligodendrocyte cell numbers.     

Maintenance of pluripotency in human embryonic stem cells cultured on a synthetic substrate in conditioned medium

Realizing the potential clinical and industrial applications of human embryonic stem cells (hESCs) is limited by the need for costly, labile, or undefined growth substrates. Here we demonstrate that trypsin passaging of the hESC lines, HUES7 and NOTT1, on oxygen plasma etched tissue culture polystyrene (PE‐TCPS) in conditioned medium is compatible with pluripotency. This synthetic culture surface is stable at room temperature for at least a year and is readily prepared by placing polystyrene substrates in a radio frequency oxygen plasma generator for 5 min. Modification of the polystyrene surface chemistry by plasma etching was confirmed by X‐ray photoelectron spectroscopy (XPS) and time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS), which identified elemental and molecular changes as a result of the treatment. Pluripotency of hESCs cultured on PE‐TCPS was gauged by consistent proliferation during serial passage, expression of stem cell markers (OCT4, TRA1‐60, and SSEA‐4), stable karyotype and multi‐germlayer differentiation in vitro, including to pharmacologically responsive cardiomyocytes. Generation of cost‐effective, easy‐to‐handle synthetic, defined, stable surfaces for hESC culture will expedite stem cell use in biomedical applications. Biotechnol. Bioeng. 2010;105: 130–140. © 2009 Wiley Periodicals, Inc.