1.Plasmodesmata Localizing Proteins Regulate Transport and Signaling during Systemic Acquired Immunity in Plants.
Lim GH1, Shine MB1, de Lorenzo L2, Yu K1, Cui W3, Navarre D4, Hunt AG2, Lee JY3, Kachroo A5, Kachroo P6. Cell Host Microbe. 2016 Apr 13;19(4):541-549. doi: 10.1016/j.chom.2016.03.006.
Systemic acquired resistance (SAR) in plants is mediated by the signaling molecules azelaic acid (AzA), glycerol-3-phosphate (G3P), and salicylic acid (SA). Here, we show that AzA and G3P transport occurs via the symplastic route, which is regulated by channels known as plasmodesmata (PD). In contrast, SA moves via the extracytosolic apoplast compartment. We found that PD localizing proteins (PDLP) 1 and 5 were required for SAR even though PD permeability in pdlp1 and 5 mutants was comparable to or higher than wild-type plants, respectively. Furthermore, PDLP function was required in the recipient cell, suggesting regulatory function in SAR. Interestingly, overexpression of PDLP5 drastically reduced PD permeability, yet also impaired SAR. PDLP1 interacted with AZI1 (lipid transfer-like protein required for AzA- and G3P-induced SAR) and contributed to its intracellular partitioning. Together, these results reveal the transport routes of SAR chemical signals and highlight the regulatory role of PD-localizing proteins in SAR.
2.Dimethyl fumarate treatment induces adaptive and innate immune modulation independent of Nrf2.
Schulze-Topphoff U1, Varrin-Doyer M1, Pekarek K1, Spencer CM1, Shetty A1, Sagan SA1, Cree BA2, Sobel RA3, Wipke BT4, Steinman L5, Scannevin RH4, Zamvil SS6. Proc Natl Acad Sci U S A. 2016 Apr 13. pii: 201603907. [Epub ahead of print]
Dimethyl fumarate (DMF) (BG-12, Tecfidera) is a fumaric acid ester (FAE) that was advanced as a multiple sclerosis (MS) therapy largely for potential neuroprotection as it was recognized that FAEs are capable of activating the antioxidative transcription factor nuclear factor (erythroid-derived 2)-like 2 (Nrf2) pathway. However, DMF treatment in randomized controlled MS trials was associated with marked reductions in relapse rate and development of active brain MRI lesions, measures considered to reflect CNS inflammation. Here, we investigated the antiinflammatory contribution of Nrf2 in DMF treatment of the MS model, experimental autoimmune encephalomyelitis (EAE). C57BL/6 wild-type (WT) and Nrf2-deficient (Nrf2-/-) mice were immunized with myelin oligodendrocyte glycoprotein (MOG) peptide 35-55 (p35-55) for EAE induction and treated with oral DMF or vehicle daily. DMF protected WT and Nrf2-/-mice equally well from development of clinical and histologic EAE.
3.The Essentiality of Arachidonic Acid in Infant Development.
Hadley KB1, Ryan AS2, Forsyth S3, Gautier S4, Salem N5. Nutrients. 2016 Apr 12;8(4). pii: E216.
Arachidonic acid (ARA, 20:4n-6) is an n-6 polyunsaturated 20-carbon fatty acid formed by the biosynthesis from linoleic acid (LA, 18:2n-6). This review considers the essential role that ARA plays in infant development. ARA is always present in human milk at a relatively fixed level and is accumulated in tissues throughout the body where it serves several important functions. Without the provision of preformed ARA in human milk or infant formula the growing infant cannot maintain ARA levels from synthetic pathways alone that are sufficient to meet metabolic demand. During late infancy and early childhood the amount of dietary ARA provided by solid foods is low. ARA serves as a precursor to leukotrienes, prostaglandins, and thromboxanes, collectively known as eicosanoids which are important for immunity and immune response. There is strong evidence based on animal and human studies that ARA is critical for infant growth, brain development, and health.
4.Laser Chemistry: Nanoporous Carbons Derived from Metal-Organic Frameworks as Novel Matrices for Surface-Assisted Laser Desorption/Ionization Mass Spectrometry (Small 15/2016).
Shih YH1, Fu CP1, Liu WL1, Lin CH1, Huang HY1, Ma S2. Small. 2016 Apr;12(15):2056. doi: 10.1002/smll.201670076.
On page 2057, a Lewis acid porous carbon material with tunable hydrophilicity is prepared by temperature controlled pyrolysis of Al based metal-organic frameworks, by C.-H. Lin, H.-Y. Huang, S. Ma, and co-workers. This porous carbon highlights its low heat capacity, and high water uptake, which acts as efficient laser-absorbing matrix/sorbent for detecting trace levels of target compounds.
