Objective To determine whether aquaporin-4 (AQP4) regulates acute lesions, delayed lesions, and the associated microglial activation after cryoinjury to the brain. Methods Brain cryoinjury was applied to AQP4 knockout (KO) and wild-type mice. At 24 h and on days 7 and 14 after cryoinjury, lesion volume, neuronal loss, and densities of microglia and astrocytes were determined, and their changes were compared between AQP4 KO and wild-type mice. Results Lesion volume and neuronal loss in AQP4 KO mice were milder at 24 h following cryoinjury, but worsened on days 7 and 14, compared to those in wild-type mice. Besides, microglial density increased more, and astrocyte proliferation and glial scar formation were attenuated on days 7 and 14 in AQP4 KO mice. Conclusion AQP4 deficiency ameliorates acute lesions, but worsens delayed lesions, perhaps due to the microgliosis in the late phase.

G protein-coupled receptor 17 (GPR17), the new P2Y-like receptor, is phylogenetically related to the P2Y and cysteinyl leukotriene receptors, and responds to both uracil nucleotides and cysteinyl leukotrienes. GPR17 has been proposed to be a damage sensor in ischemic stroke; however, its role in brain inflammation needs further detailed investigation. Here, we extended previous studies on the spatiotemporal profiles of GPR17 expression and localization, and their implications for brain injury after focal cerebral ischemia. We found that in the ischemic core, GPR17 mRNA and protein levels were upregulated at both 12-24 h and 7-14 days, but in the boundary zone the levels increased 7-14 days after reperfusion. The spatiotemporal pattern of GPR17 expression well matched the acute and late (subacute/chronic) responses in the ischemic brain. According to previous findings, in the acute phase, after ischemia (24 h), upregulated GPR17 was localized in injured neurons in the ischemic core and in a few microglia in the ischemic core and boundary zone. In the late phase (14 days), it was localized in microglia, especially in activated (ED1-positive) microglia in the ischemic core, but weakly in most microglia in the boundary zone. No GPR17 was detectable in astrocytes. GPR17 knockdown by a small interfering RNA attenuated the neurological dysfunction, infarction, and neuron loss at 24 h, and brain atrophy, neuron loss, and microglial activation at 14 days after reperfusion. Thus, GPR17 might mediate acute neuronal injury and late microgliosis after focal cerebral ischemia.

Cysteinyl leukotrienes (CysLTs), potent inflammatory mediators, are released from ischemic brain, and may regulate ischemic injury through activating CysLT(1) and CysLT(2) receptors. The CysLT(1) receptor is closely associated with ischemic injury and post-ischemic repair; however, the CysLT(2) receptor-mediated responses remain unknown. Here, we investigated the spatiotemporal profiles and implications of CysLT(2) receptor expression and localization in rat brain after focal cerebral ischemia. CysLT(2) receptors were normally localized in astrocytes in the cortex and around the ventricles. After focal cerebral ischemia, CysLT(2) receptor expression was up-regulated in concert with neuronal and glial responses. In the acute phase (6-24 h), up-regulated CysLT(2) receptors were restricted to injured neurons in the ischemic core; while in the late phase (3-28 days), the up-regulation was restricted to hypertrophic microglia (ischemic core) and mainly localized in hypertrophic astrocytes (boundary zone). Thus, the spatiotemporal profiles of CysLT(2) receptor expression suggest that it plays regulatory roles in acute neuron injury, and astrocytosis and microgliosis in the late phase.

Late embryogenesis abundant (LEA) protein family is a large protein family that includes proteins accumulated at late stages of seed development or in vegetative tissues in response to drought, salinity, cold stress and exogenous application of abscisic acid. In order to isolate peanut genes, an expressed sequence tag (EST) sequencing project was carried out using a peanut seed cDNA library. From 6258 ESTs, 19 LEA-encoding genes were identified and could be classified into eight distinct groups. Expression of these genes in seeds at different developmental stages and in various peanut tissues was analysed by semi-quantitative RT-PCR. The results showed that expression levels of LEA genes were generally high in seeds. Some LEA protein genes were expressed at a high level in non-seed tissues such as root, stem, leaf, flower and gynophore. These results provided valuable information for the functional and regulatory studies on peanut LEA genes.

Peanut (Arachis hypogaea L.) is one of the most important oil crops in the world. However, biotechnological based improvement of peanut is far behind many other crops. It is critical and urgent to establish the biotechnological platform for peanut germplasm innovation. In this study, a peanut seed cDNA library was constructed to establish the biotechnological platform for peanut germplasm innovation. About 17,000 expressed sequence tags (ESTs) were sequenced and used for further investigation. Among which, 12.5% were annotated as metabolic related and 4.6% encoded transcription or post-transcription factors. ESTs encoding storage protein and enzymes related to protein degradation accounted for 28.8% and formed the largest group of the annotated ESTs. ESTs that encoded stress responsive proteins and pathogen-related proteins accounted for 5.6%. ESTs that encoded unknown proteins or showed no hit in the GenBank nr database accounted for 20.1% and 13.9%, respectively. A total number of 5066 EST sequences were selected to make a cDNA microarray. Expression analysis revealed that these sequences showed diverse expression patterns in peanut seeds, leaves, stems, roots, flowers, and gynophores. We also analyzed the gene expression pattern during seed development. Genes that were upregulated (≥twofold) at 15, 25, 35, and 45 days after pegging (DAP) were found and compared with 70 DAP. The potential value of these genes and their promoters in the peanut gene engineering study is discussed.

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality, but the cellular and molecular mechanisms are still not fully understood. Type II pneumocytes are identified as the synthesizing cells of the alveolar surfactant, which has important properties in maintaining alveolar and airway stability. Lung surfactant can reduce the surface tension and prevent alveolar collapse and the airway walls collapse. Pulmonary surfactant components play important roles in normal lung function and inflammation in the lung. Surfactant has furthermore been shown to modulate the process of innate host defense, including suppression of cytokine secretion and transcription factor activation, in the inflammatory network of COPD. Abnormalities of lung surfactant might be one of the mechanisms leading to increased airway resistance in COPD. The increased expression of Granzyme A and B was found in lung tissues of patients with COPD and type II pneumocytes was proposed to be involved in the pathogenesis of COPD. These novel findings provide new sights into the role of the type II pneumocytes in the pathogenesis of COPD.

BACKGROUND: MicroRNAs (miRNAs) are a new class of small, endogenous RNAs that play a regulatory role in the cell by negatively affecting gene expression at the post-transcriptional level. miRNAs have been shown to control numerous genes involved in various biological and metabolic processes. There have been extensive studies on discovering miRNAs and analyzing their functions in model species, such as Arabidopsis and rice. Increasing investigations have been performed on important agricultural crops including soybean, conifers, and Phaselous vulgaris but no studies have been reported on discovering peanut miRNAs using a cloning strategy. RESULTS: In this study, we employed the next generation high through-put Solexa sequencing technology to clone and identify both conserved and species-specific miRNAs in peanuts. Next generation high through-put Solexa sequencing showed that peanuts have a complex small RNA population and the length of small RNAs varied, 24-nt being the predominant length for a majority of the small RNAs. Combining the deep sequencing and bioinformatics, we discovered 14 novel miRNA families as well as 75 conserved miRNAs in peanuts. All 14 novel peanut miRNAs are considered to be species-specific because no homologs have been found in other plant species except ahy-miRn1, which has a homolog in soybean. qRT-PCR analysis demonstrated that both conserved and peanut-specific miRNAs are expressed in peanuts. CONCLUSIONS: This study led to the discovery of 14 novel and 22 conserved miRNA families from peanut. These results show that regulatory miRNAs exist in agronomically important peanuts and may play an important role in peanut growth, development, and response to environmental stress.

OBJECTIVE: To prepare and identify a polyclonal antibody against cysteinyl leukotriene receptor (CysLT(2)receptor). METHODS: Rabbits were immunized with KLH-coupled CysLT(2)receptor peptide to prepare the polyclonal antibody (pAb). The titer of the pAb in rabbit plasma was detected by indirect ELISA, and the specificity of the pAb was tested by antigen blockade. The tissue distribution of CysLT(2) receptor was detected by Western blot and immunohistochemistry with the prepared pAb. RESULT: The pAb showed a titer higher than 1/1047296, and was specific to CysLT(2) receptor, without cross-reaction with the antigens of CysLT(1) receptor and GPR17. A higher expression of CysLT(2) receptor in kidney, brain and lung of rats and mice was detected by Western blot analysis using the prepared pAb. The molecular weight of CysLT(2) receptor protein was about 40 kD. Immunohistochemical examination showed that CysLT(2) receptor was expressed mainly in the neuron, and partly in astrocytes in rat brain. CONCLUSION: The prepared CysLT(2) receptor pAb has high sensitivity and specificity, and can be used in Western blot and immunohistochemistry.

A silicon-on insulator (SOI) zero-gap directional coupler switch is studied based on the large-cross-section singlemode rib waveguide condition, the dual-mode interference principle, and the free-carrier plasma dispersion effect, in which the SOI technique uses silicon and silicon dioxide thermal bonding and backpolishing. The SOI is fabricated by potassium hydroxide anisotropic etching. Its insertion loss and cross talk are measured to be less than 4.81 dB and 218.6 dB, respectively, at a wavelength of 1.3 microm and a switching voltage of 0.91 V. Response time is ~210 ns.

OBJECTIVE: To prepare and identify a polyclonal antibody (pAb) against GPR17, a novel cysteinyl leukotriene receptor. METHODS: Rabbits were immunized with KLH-coupled GPR17 peptide to prepare the pAb. The titer of the pAb in rabbit plasma was detected by indirect ELISA, and the specificity of the pAb was tested by antigen blockade. GPR17 tissue distribution was detected by Western blot with the pAb. RESULTS: The pAb showed a titer as high as 1:16 364,and was not cross-reacted with the antigens of CysLT(1) and CysLT(2) receptors. A higher expression of GPR17 in the rat brain and heart was detected using the newly prepared pAb. The molecular weigh of GPR17 protein was about 43 kD. CONCLUSION: The prepared GPR17 pAb has high sensitivity and specificity,and can be used in Western blot for detecting GPR17.