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Global agriculture loses over $100 billion of produce annually to crop pests such as insects. Many of these crop pests either are not currently controlled by artificial means or have developed resistance against chemical pesticides. Long dsRNAs are capable of inducing RNAi in insects and are emerging as novel, highly selective alternatives for sustainable insect management strategies. However, there are significant challenges associated with RNAi efficacy in insects. In this study, we synthesized a range of chemically modified long dsRNAs in an approach to improve nuclease resistance and RNAi efficacy in insects. Our results showed that dsRNAs containing phosphorothioate modifications demonstrated increased resistance to southern green stink bug saliva nucleases. Phosphorothioate-modified and 2'-fluoro-modified dsRNA also demonstrated increased resistance to degradation by soil nucleases and increased RNAi efficacy in Drosophila melanogaster cell cultures. In live insects, we found chemically modified long dsRNAs successfully resulted in mortality in both stink bug and corn rootworm. These results provide further mechanistic insight into the dependence of RNAi efficacy on nucleotide modifications in the sense or antisense strand of the dsRNA in insects and demonstrate for the first time that RNAi can successfully be triggered by chemically modified long dsRNAs in insect cells or live insects., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Autosomal dominant polycystic kidney disease (ADPKD) is a very common inherited disease caused by mutations in PKD1 or PKD2 genes characterized by progressive enlargement of fluid-filled cysts and loss of renal function [1]. Previous studies proposed a role for human polycystin-1 in renal morphogenesis acting as a matrix receptor in focal adhesions and for polycystin-2 as a putative calcium channel [2, 3]. The genome of Caenorhabditis elegans contains 2 new members of the polycystin family: lov-1, the homolog for PKD1; and pkd-2, the homolog for PKD2 [4; this paper]. Mutation analysis in C. elegans showed similarly compromised male mating behaviors in all single and double lov-1 and pkd-2 mutants, indicating their participation in a single genetic pathway. Expression analysis localized LOV-1 and PKD-2 to the ends of sensory neurons in male tails and to the tips of CEM neurons in the head, consistent with functions as chemo- or mechanosensors. Human and C. elegans PKD1 and PKD2 homologs, transfected into mammalian renal epithelial cells, co-localized with paxillin in focal adhesions suggesting function in a single biological pathway. Based on the role of polycystins in C. elegans sensory neuron function and the conservation of PKD pathways we suggest that polycystins act as sensors of the extracellular environment, initiating, via focal adhesion assembly, intracellular transduction events in neuronal or morphogenetic processes., (Copyright 2003 S. Karger AG, Basel)

A novel transmembrane protein (designated X7365) containing two follistatin modules and an epidermal growth factor (EGF) domain has been described in the hypothalamic-pituitary axis of Xenopus laevis. We have now cloned the highly conserved mouse orthologue (M7365), and its mRNA was detected in many mesodermal and (neuro)ectodermal tissues in 8.5-day-old mouse embryos. During further development, M7365 mRNA expression became restricted to certain regions in the brain and to ganglia. In the adult mouse, the brain is the major site of M7365 expression.

SMAD proteins are downstream targets of serine/threonine kinase receptors of the transforming growth factor beta (TGF beta) superfamily. Ligands activating these receptors regulate cell growth, differentiation and development in many tissues of various organisms. In mammals eight different Smad genes are known, each with different roles in mediating signalling between plasma membrane and nucleus. Smad6 and Smad7 are inhibitors of TGF beta family signalling. They are both expressed in human adult vascular endothelial cells, particularly after these cells have been subjected to shear stress (Topper et al. [1997] Proc Natl Acad Sci USA 94:9314-9319). Here we show by reverse transcriptase polymerase chain reaction and in situ hybridization that Smad7 mRNA is highly expressed in the developing vascular system of the mouse embryo but is also detectable much earlier in preimplantation embryos and during gastrulation. We also demonstrate by transient transgenesis that overexpression of Smad7 in mouse zygotes inhibits development beyond the 2-cell stage. This confirms earlier conclusions of similar, but complementary, experiments using a dominant negative type II TGF beta receptor demonstrating that TGF beta signalling is required for normal preimplantation development., (Copyright 2000 Wiley-Liss, Inc.)

CD40 belongs to the tumor necrosis factor (TNF) receptor family. CD40 signaling involves the recruitment of TNF receptor-associated factors (TRAFs) to its cytoplasmic domain. We have identified a novel intracellular CD40-binding protein termed TRAF and TNF receptor-associated protein (TTRAP) that also interacts with TNF-R75 and CD30. The region of the CD40 cytoplasmic domain that is required for TTRAP association overlaps with the TRAF6 recognition motif. Association of TTRAP with CD40 increases profoundly in response to treatment of cells with CD40L. Interestingly, TTRAP also associates with TRAFs, with the highest affinity for TRAF6. In transfected cells, TTRAP inhibits in a dose-dependent manner the transcriptional activation of a nuclear factor-kappaB (NF-kappaB)-dependent reporter mediated by CD40, TNF-R75 or Phorbol 12-myristate 13-acetate (PMA) and to a lesser extent by TRAF2, TRAF6, TNF-alpha, or interleukin-1beta (IL-1beta). TTRAP does not affect stimulation of NF-kappaB induced by overexpression of the NF-kappaB-inducing kinase (NIK), the IkappaB kinase alpha (IKKalpha), or the NF-kappaB subunit P65/RelA, suggesting it acts upstream of the latter proteins. Our results indicate that we have isolated a novel regulatory factor that is involved in signal transduction by distinct members of the TNF receptor family.

Activins exert their effects by inducing heteromeric complexes of either of two different type I receptors, ActR-I or ActR-IB, and either of two type II receptors, ActR-II or ActR-IIB. We describe the cDNA cloning of the mouse homologue of human ActR-IB and analyze binding of radio-iodinated activin on type I/type II combinations of mouse receptors expressed from cDNA. We studied the distribution of ActR-I and ActR-IB mRNAs in postimplantation mouse embryos by in situ hybridization. In the 12.5-day postcoitum embryo, both mRNAs are found in the brain, spinal cord, some ganglia, vibrissae, lungs, body wall, stomach, gonads, ribs, limbs and shoulders. ActR-I mRNA, but not ActR-IB, is expressed in blood vessels, the heart, tongue, intervertebral discs and diaphragm. Conversely, only ActR-IB mRNA is detected in the olfactory region, eye, tooth primordium, esophagus, mesonephros, dorsal root ganglia and is strongly expressed in the spinal cord. Our results demonstrate similarities, but also differences and complementarities (mesenchymal versus epithelial expression) between the expression patterns of these type I receptors. Moreover, their expression patterns overlap with at least one of the type II activin receptors and/or one of activin subunits in some regions of the embryo, such as the brain, spinal cord, pituitary, whisker follicles, and the inner nuclear neuroblastic layer of the eye.