Identification and Functional Characterization of Powdery Mildew Effectors

The ascomycete Blumeria graminis f.sp. hordei (Bgh) is the causal agent of the powdery mildew disease of the monocot barley (Hordeum vulgare). Suppression of host defense responses and accommodation of the intracellular feeding structure (haustorium) are indispensable for this obligate biotrophic phytopathogen. To manipulate its host plant, Bgh presumably employs small, secreted effector proteins. We bioinformatically identified effector candidates from the barley powdery mildew fungus by screening publicly available EST databases for cDNAs encoding small, secreted proteins of unknown function. A subset of these effector candidates (ECs) enhanced Bgh haustorium formation upon transient expression in barley cells. EC proteins are encoded by single-copy genes, are sequence conserved among different Bgh isolates and exhibit distinct expression patterns during fungal pathogenesis. Plant interacting proteins for two of the effector candidates were identified by a yeast two-hybrid screen in a barley cDNA library. EC4 interacts with a barley thiopurine methyltransferase (HvTPMT) whereas EC6 interacts with a barley ubiquitin conjugating enzyme (HvUBC-E2). Both interactions were confirmed in planta by bimolecular fluorescence complementation, suggesting that EC4 might target the host vesicle trafficking pathway while EC6 might be involved in controlling the synthesis of a yet unknown volatile compatibility compound. We also identified a multigene family encoding putative secreted RNase-like effectors in the Bgh genome. The RNase-like proteins are highly polymorphic and fulfill the proposed criteria for Bgh effectors that are recognized by barley MLA resistance proteins (avirulence canidates (ACs)). We isolated a range of AC cDNAs from two Bgh isolates and tested a subset of them for their avirulence function. The results of these experiments do not support an avirulence function for the AC proteins so far

The Impact of Professional Development on Reading Achievement and Teacher Efficacy in Delivering Small Group Reading Instruction

Literacy is an equity issue of significant importance; students who do not read on grade level by the end of third grade are more likely to drop out of high school and less likely to attend post-secondary education (Lesnick, Goerge, Smithgall, & Gwynne, 2010). Early interventions in Kindergarten through second grade can ameliorate problems which struggling readers experience (Torgesen, 2004). Teachers are poorly prepared to provide the type of intervention instruction necessary to assist these struggling students (Birman, Desimone, Porter, & Garet, 2000; Neuman & Cunningham, 2009). The purpose of this mixed-methods participatory action research study was to examine the effects of professional development designed on principles of effectiveness and factors influencing self-efficacy on student reading achievement and self-efficacy beliefs of participating teachers in K through second grade. A dependent sample t-test showed students of teachers participating in professional development demonstrated statistically significant increases in reading achievement, as measured by the PALs concept of word assessments and guided reading level. The Teachers’ Sense of Efficacy for Literacy Instruction (TSELI) instrument assessed teachers feelings of efficacy pre and post training; a dependent sample t-test demonstrated teachers experienced statistically significant increases in literacy self-efficacy. Interview data indicated that the verbal persuasion, vicarious and mastery experiences from the professional development impacted their feelings of self-efficacy. Recommendations include: implement future professional development based on the study model; train remaining teachers in the same manner; employ a part-time literacy supervisor to ensure fidelity going forward

Do you mind when people sit on your lap and take pictures?

Abbot Pennings answers questions about his feelings about students climbing on his statue (before it was placed in the Miriam B. and James J. Mulva Library), archived from SNC website

Flares in Open Clusters with K2. I. M45 (Pleiades), M44 (Praesepe) and M67

The presence and strength of a stellar magnetic field and activity is rooted in a star's fundamental parameters such as mass and age. Can flares serve as an accurate stellar "clock"? To explore if we can quantify an activity-age relation in the form of a flaring-age relation, we measured trends in the flaring rates and energies for stars with different masses and ages. We investigated the time-domain photometry provided by Kepler's follow-up mission K2 and searched for flares in three solar metallicity open clusters with well-known ages, M45 (0.125 Gyr), M44 (0.63 Gyr), and M67 (4.3 Gyr). We updated and employed the automated flare finding and analysis pipeline Appaloosa, originally designed for Kepler. We introduced a synthetic flare injection and recovery subroutine to ascribe detection and energy recovery rates for flares in a broad energy range for each light curve. We collected a sample of 1 761 stars, mostly late-K to mid-M dwarfs and found 751 flare candidates with energies ranging from $4\cdot10^{32}$ erg to $6\cdot10^{34}$ erg, of which 596 belong to M45, 155 to M44, and none to M67. We find that flaring activity depends both on $T_\mathrm{eff}$, and age. But all flare frequency distributions have similar slopes with $\alpha \approx2.0-2.4$, supporting a universal flare generation process. We discuss implications for the physical conditions under which flares occur, and how the sample's metallicity and multiplicity affect our results.Comment: 17 pages, 11 figures, appendix. Accepted to A&

Sbf/MTMR13 coordinates PI(3)P and Rab21 regulation in endocytic control of cellular remodeling.

Cells rely on the coordinated regulation of lipid phosphoinositides and Rab GTPases to define membrane compartment fates along distinct trafficking routes. The family of disease-related myotubularin (MTM) phosphoinositide phosphatases includes catalytically inactive members, or pseudophosphatases, with poorly understood functions. We found that Drosophila MTM pseudophosphatase Sbf coordinates both phosphatidylinositol 3-phosphate (PI(3)P) turnover and Rab21 GTPase activation in an endosomal pathway that controls macrophage remodeling. Sbf dynamically interacts with class II phosphatidylinositol 3-kinase and stably recruits Mtm to promote turnover of a PI(3)P subpool essential for endosomal trafficking. Sbf also functions as a guanine nucleotide exchange factor that promotes Rab21 GTPase activation associated with PI(3)P endosomes. Of importance, Sbf, Mtm, and Rab21 function together, along with Rab11-mediated endosomal trafficking, to control macrophage protrusion formation. This identifies Sbf as a critical coordinator of PI(3)P and Rab21 regulation, which specifies an endosomal pathway and cortical control