ABSTRACT
Nervous wreck (Nwk), a protein that is present at Type 1 glutamatergic synapses that contains an SH3 domain and an FCH motif, is a Drosophila homolog of the human srGAP3/MEGAP protein, which is associated with mental retardation. Confocal microscopy revealed that circles in Nwk reticulum enclosed T-shaped active zones (T-AZs) and partially colocalized with synaptic vesicle (SV) markers and both exocytosis and endocytosis components. Results from an electron microscopic (EM) analysis showed that Nwk proteins localized at synaptic edges and in SV pools. Both the synaptic areas and the number of SVs in the readily releasable (RRPs) and reserve (RPs) SV pools in nwk2 were significantly reduced. Synergistic, morphological phenotypes observed from eag¹;nwk² neuromuscular junctions suggested that Nwk may regulate synaptic plasticity differently from activity-dependent Hebbian plasticity. Although the synaptic areas in eag¹;nwk² boutons were not significantly different from those of nwk², the number of SVs in the RRPs was similar to those of Canton-S. In addition, three-dimensional, high-voltage EM tomographic analysis demonstrated that significantly fewer enlarged SVs were present in nwk² RRPs. Furthermore, Nwk formed protein complexes with Drosophila Synapsin and Synaptotagmin 1 (DSypt1). Taken together, these findings suggest that Nwk is able to maintain synaptic architecture and both SV size and distribution at T-AZs by interacting with Synapsin and DSypt1.
ABSTRACT
PURPOSE: Obtaining brain tissue is critical to definite diagnosis and to furthering understanding of neurodegenerative diseases. The present authors have maintained the National Neuropathology Reference and Diagnostic Laboratories for Dementia in South Korea since 2016. We have built a nationwide brain bank network and are collecting brain tissues from patients with neurodegenerative diseases. We are aiming to facilitate analyses of clinic-pathological and image-pathological correlations of neurodegenerative disease and to broaden understanding thereof. MATERIALS AND METHODS: We recruited participants through two routes: from memory clinics and the community. As a baseline evaluation, clinical interviews, a neurological examination, laboratory tests, neuropsychological tests, and MRI were undertaken. Some patients also underwent amyloid PET. RESULTS: We recruited 105 participants, 70 from clinics and 35 from the community. Among them, 11 died and were autopsied. The clinical diagnoses of the autopsied patients included four with Alzheimer's disease (AD), two with subcortical vascular dementia, two with non-fluent variant primary progressive aphasia, one with leukoencephalopathy, one with frontotemporal dementia (FTD), and one with Creutzfeldt-Jakob disease (CJD). Five patients underwent amyloid PET: two with AD, one with mixed dementia, one with FTD, and one with CJD. CONCLUSION: The clinical and neuropathological information to be obtained from this cohort in the future will provide a deeper understanding of the neuropathological mechanisms of cognitive impairment in Asia, especially Korea.
Subject(s)
Humans , Alzheimer Disease , Amyloid , Aphasia, Primary Progressive , Asia , Brain , Cognition Disorders , Cohort Studies , Creutzfeldt-Jakob Syndrome , Dementia , Dementia, Vascular , Diagnosis , Frontotemporal Dementia , Korea , Leukoencephalopathies , Magnetic Resonance Imaging , Memory , Neurodegenerative Diseases , Neurologic Examination , Neuropathology , Neuropsychological TestsABSTRACT
BACKGROUND: It has generally been proven that histone acetylation and deacetylation are involved in the malignant transformation. To date, however, this has rarely been studied in cases of malignant lymphoma. METHODS: We studied nine cases of reactive lymphoid hyperplasia, 78 cases of diffuse large B-cell lymphoma (DLBCL), 13 cases of peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), and 13 cases of extranodal NK/T-cell lymphoma, nasal type (NKTCL). Thus, we attempted to elucidate the associations of the degree of the expression of histone acetyltransferase 1 (HAT1), histone deacetylase (HDAC) 1, HDAC2, and HDAC3 with the clinical behaviors of above malignant lymphomas using the immunohistochemistry and a western blot analysis. RESULTS: The degree of the expression of HAT1 was higher in cases of DLBCL, PTCL-NOS or NKTCL as compared with reactive lymphoid hyperplasia (p0.05). CONCLUSIONS: HAT1, HDAC1, and HDAC2 play a critical role in the development of malignant lymphomas. Both HAT1 and HDAC1 might be indicators for a poor prognosis in cases of DLBCL as cooperating factors.