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Hessler, G.

Publications and source records attributed to Hessler, G..

3 recordsLinked to original sources

Deep Batch Active Learning for Drug Discovery

A key challenge in drug discovery is to optimize, in silico, various absorption and affinity properties of small molecules. One strategy that was proposed for such optimization process is active learning. In active learning molecules are selected for testing based on their likelihood of improving model performance. To enable the use of active learning with advanced neural network models we developed two novel active learning batch selection methods. These methods were tested on several public datasets for different optimization goals and with different sizes. We have also curated new affinity datasets that provide chronological information on state-of-the-art experimental strategy. As we show, for all datasets the new active learning methods greatly improved on existing and current batch selection methods leading to significant potential saving in the number of experiments needed to reach the same model performance. Our methods are general and can be used with any package including the popular DeepChem library.

bioinformatics↗

TIR-catalyzed ADP-ribosylation reactions produce signaling molecules for plant immunity

Plant pathogen-activated immune signaling by nucleotide-binding leucine-rich repeat (NLR) receptors with an N-terminal Toll/Interleukin-1 receptor (TIR) domain converges on Enhanced Disease Susceptibility 1 (EDS1) and its direct partners Phytoalexin Deficient 4 (PAD4) or Senescence-Associated Gene 101 (SAG101). TIR-encoded NADases produce signaling molecules to promote exclusive EDS1-PAD4 and EDS1-SAG101 interactions with helper NLR sub-classes. Here we show that TIR-containing proteins catalyze adenosine diphosphate (ADP)-ribosylation of adenosine triphosphate (ATP) and ADP ribose (ADPR) via ADPR polymerase-like and NADase activity, forming ADP-ribosylated ATP (ADPr-ATP) and ADPr-ADPR (di-ADPR), respectively. Specific binding of di-ADPR or ADPr-ATP allosterically promotes EDS1-SAG101 interaction with helper NLR N requirement gene 1A (NRG1A) in vitro and in planta. Our data reveal an enzymatic activity of TIRs that enables specific activation of the EDS1-SAG101-NRG1 immunity branch.

plant biology↗

Identification and receptor mechanism of TIR-catalyzed small molecules in plant immunity

Plant nucleotide-binding leucine-rich-repeat receptors (NLRs) with an N-terminal toll/interleukin-1 receptor (TIR) domain sense pathogen effectors to enable TIR-encoded NADase activity for immune signaling. TIR-NLR (TNL) signaling requires conserved helper NLRs NRG1 and ADR1 and the lipase-like protein EDS1 that functions as a heterodimer with each of its paralogs PAD4 and SAG101. We show that TIR-containing proteins catalyze production of 2-(5-phosphoribosyl)-5-adenosine mono-/di-phosphate (pRib-AMP/ADP) in vitro and in planta. Biochemical and structural data demonstrate that EDS1-PAD4 is a receptor complex for pRib-AMP/ADP. pRib-ADP binding triggers a conformational change in the PAD4 C-terminal domain to allosterically promote EDS1-PAD4 interaction with ADR1-L1 but not NRG1A. Our study identifies TIR-catalyzed pRib-AMP/ADP as a missing link in TIR signaling via EDS1-PAD4 and as likely second messengers for plant immunity.

plant biology↗