Biological and biochemical functions of immunity transcription factor NF-κB in basal metazoans are largely unknown. Herein, we characterize transcription factor NF-κB from the demosponge Amphimedon queenslandica (Aq), in the phylum Porifera. Structurally and phylogenetically, the Aq-NF-κB protein is most similar to NF-κB p100 and p105 among vertebrate proteins, with an Nterminal DNA-binding/dimerization domain, a C-terminal Ankyrin (ANK) repeat domain, and a DNA binding-site profile more similar to human NF-κB proteins than Rel proteins. Aq-NF-κB also resembles the mammalian NF-κB protein p100 in that C-terminal truncation results in translocation of Aq-NF-κB to the nucleus and increases its transcriptional activation activity. Overexpression of a human or sea anemone IκB kinase (IKK) can induce C-terminal processing of Aq-NF-κB in vivo, and this processing requires C-terminal serine residues in Aq-NF-κB. Unlike human NF-κB p100, however, the C-terminal sequences of Aq-NF-κB do not effectively inhibit its DNAbinding activity when expressed in human cells. Tissue of another demosponge, a black encrusting sponge, contains NF-κB site DNAbinding activity and an NF-κB protein that appears mostly processed and in the nucleus of cells. NF-κB DNA-binding activity and processing is increased by treatment of sponge tissue with LPS. By transcriptomic analysis of A. queenslandica we identified likely homologs to many upstream NF-κB pathway components. These results present a functional characterization of the most ancient metazoan NF-κB protein to date, and show that many characteristics of mammalian NF-κB are conserved in sponge NF-κB, but the mechanism by which NF-κB functions and is regulated in the sponge may be somewhat different.
We compared auditory, cognitive, and language test results in a pair of dizygotic twins, one of whom showed symptoms of central auditory processing disorder (CAPD). Results highlight the importance of testing binaural function. In particular, electrophysiologic measures of dichotic listening effectively demonstrated the auditory-specific nature of this child's listening problems. The importance of a thorough and comprehensive evaluation of children suspected of CAPD is stressed.
Abbreviations: ABR = auditory brainstem response, CAPD = central auditory processing disorder, CELF = Clinical Evaluation of Language Functions, ERP = event-related potential, PPST = Pitch Pattern Sequence Test, PST = Phonemic Synthesis Test, RASP = Rapidly Alternating Speech Perception, SCAN = Screening Test for Auditory Processing, SSW = Staggered Spondaic Word Test, TTC = Token Test for Children, WISC-III = Wechsler Intelligence Scale for Children-III
Intraoperative cranial nerve neuromonitoring (IONM) has significantly reduced morbidity historically associated with skull-base procedures. It provides the surgeon with immediate feedback to preserve both anatomic and physiologic function of monitored nerves. However, when the surgeon cauterizes tissue near the nerve, the monitoring equipment is saturated by the cautery signal, eliminating IONM information at a critical time. The use of an infrared camera under the drapes to observe the face for movement due to nerve stimulation is an invaluable adjunct to traditional IONM. Monitoring may also be improved by contralateral electrode placement to help identify artifact from nerve stimulation, using the microscope's video output to compare the surgeon's hand movements to recorded activity, and learning basic anatomy of the inner ear and skull base in order to know when heightened attention is important.KEY WORDS. Acoustic neuroma, facial nerve monitoring, infrared camera, intraoperative neuromonitoring, skull-base procedures, vestibular nerve.
The objective of this study was to assess the effects of different methods of sternocleidomastoid muscle (SCM) activation on vestibular evoked myogenic potentials (VEMP). Forty normal volunteers were tested using three different methods of SCM activation: sitting with the head turned away from the test ear (SIT), supine with the head held straight up (SHU), and supine with the head held up and turned away from the test ear (SHT). Dependent measures were latency, and amplitude. Head and body position significantly affected the amplitude of the VEMP, but had no significant effect on latency. Testing subjects in the supine position with the head up and turned toward the non-test ear yielded the most robust amplitude response and sternocleidomastoid EMG activity. When amplitude measures where corrected according to tonic electromyographic (EMG) activity no significant difference was noted between the three different test positions. The increased amplitude in the supine with head turned position can be directly attributed to increased tonic SCM EMG activity.
Cell wall recalcitrance is a major constraint for the exploitation of lignocellulosic biomass as a renewable resource for energy and bio-based products. Transcriptional regulators of the lignin biosynthetic pathway represent promising targets for tailoring lignin content and composition in plant secondary cell walls. However, knowledge about the transcriptional regulation of lignin biosynthesis in lignocellulosic feedstocks, such as Miscanthus, is limited. In Miscanthus leaves, MsSCM1 and MsMYB103 are expressed at growth stages associated with lignification. The ectopic expression of MsSCM1 and MsMYB103 in N. benthamiana leaves was sufficient to trigger secondary cell wall deposition with distinct sugar and lignin compositions. Moreover, RNA-seq analysis revealed that the transcriptional responses to MsSCM1 and MsMYB103 overexpression showed an extensive overlap with the response to the NAC master transcription factor MsSND1, but were distinct from each other, underscoring the inherent complexity of secondary cell wall formation. Furthermore, conserved and previously described promoter elements as well as novel and specific motifs could be identified from the target genes of the three transcription factors. Together, MsSCM1 and MsMYB103 represent interesting targets for manipulations of lignin content and composition in Miscanthus towards a tailored biomass.
38 Cell wall recalcitrance is a major constraint for the exploitation of lignocellulosic biomass as 39 renewable resource for energy and bio-based products. Transcriptional regulators of the lignin 40 biosynthetic pathway represent promising targets for tailoring lignin content and composition in 41 plant secondary cell walls. A wealth of research in model organisms has revealed that 42 transcriptional regulation of secondary cell wall formation is orchestrated by a hierarchical 43 transcription factor (TF) network with NAC TFs as master regulators and MYB factors in the lower 44 tier regulators. However, knowledge about the transcriptional regulation of lignin biosynthesis in 45 lignocellulosic feedstocks, such as Miscanthus, is limited. Here, we characterized two Miscanthus 46 MYB TFs, MsSCM1 and MsMYB103, and compared their transcriptional impact with that of the 47 master regulator MsSND1. In Miscanthus leaves MsSCM1 and MsMYB103 are expressed at 48 growth stages associated with lignification. Ectopic expression of MsSCM1 and MsMYB103 in 49 tobacco leaves was sufficient to trigger secondary cell wall deposition with distinct sugar and lignin 50 composition. Moreover, RNA-seq analysis revealed that the transcriptional responses to MsSCM1 51 and MsMYB103 overexpression showed extensive overlap with the response to MsSND1, but 52 were distinct from each other, underscoring the inherent complexity of secondary cell wall 53 formation. Together, MsSCM1 and MsMYB103 represent interesting targets for manipulations of 54 lignin content and composition in Miscanthus towards tailored biomass. 55 56 157 158 Tissue Staining and Microscopy 159
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