1
|
Law CY, Lam CW. C-terminal truncated SPOP, a Janus-faced variant, causing a mixed type 1 and type 2 Nabais Sa-de Vries syndrome. Clin Chim Acta 2022; 535:187-194. [PMID: 36063898 DOI: 10.1016/j.cca.2022.08.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 08/09/2022] [Accepted: 08/19/2022] [Indexed: 11/26/2022]
Abstract
Nabais Sa-de Vries syndrome (NSDVS) is an autosomal dominant neurodevelopmental disorder first described in 2020 and is classified into type 1 (NSDVS1) and type 2 (NSDVS2) which encompassed of spectrum of distinct clinical features due to gain-of-function (GOF) and loss-of-function (LOF) variants respectively. So far only 6 cases of 5 different missense pathogenic variants had been reported which impact on the SPOP substrate binding affinity for the downstream ubiquitylation. Here, we report a novel and de novo heterozygous nonsense pathogenic variant, p.Tyr353Term at the BACK domain in a patient with neurodevelopmental delay plus mixed phenotypes of NSDVS type 1 and 2 using trio exome analysis. The BACK domain is functionally critical for the SPOP higher-order oligomerization and is shown to increase substrate binding avidity with enhanced ubiquitylation efficiency in vitro. Experimentally, a missense variant p.Tyr353Glu is proven to attenuate the tandem SPOP oligomer formation and we envisage the current truncated variant at the same residue would attenuate the oligomerization process. This is the first report providing in vivo clue about the clinical significance of SPOP oligomerization in human neurodevelopmental disorders with new understanding on the expanding spectrum of NSDVS. We conclude the p.Tyr353Term is a Janus-faced variant which explains the dual NSDVS type 1 and 2 phenotypes in this case.
Collapse
Affiliation(s)
- Chun-Yiu Law
- Division of Chemical Pathology, Department of Pathology, Queen Mary Hospital, Hong Kong Special Administrative Region
| | - Ching-Wan Lam
- Division of Chemical Pathology, Department of Pathology, Queen Mary Hospital, Hong Kong Special Administrative Region; Department of Pathology, The University of Hong Kong, Hong Kong Special Administrative Region.
| |
Collapse
|
2
|
Wang C, Xu Q, Zhang X, Day DS, Abraham BJ, Lun K, Chen L, Huang J, Ji X. BRD2 interconnects with BRD3 to facilitate Pol II transcription initiation and elongation to prime promoters for cell differentiation. Cell Mol Life Sci 2022; 79:338. [PMID: 35665862 PMCID: PMC11072765 DOI: 10.1007/s00018-022-04349-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 04/20/2022] [Accepted: 05/04/2022] [Indexed: 11/03/2022]
Abstract
The bromodomain and extraterminal motif (BET) proteins are critical drug targets for diseases. The precise functions and relationship of BRD2 with other BET proteins remain elusive mechanistically. Here, we used acute protein degradation and quantitative genomic and proteomic approaches to investigate the primary functions of BRD2 in transcription. We report that BRD2 is required for TAF3-mediated Pol II initiation at promoters with low levels of H3K4me3 and for R-loop suppression during Pol II elongation. Single and double depletion revealed that BRD2 and BRD3 function additively, independently, or perhaps antagonistically in Pol II transcription at different promoters. Furthermore, we found that BRD2 regulates the expression of different genes during embryonic body differentiation processes by promoter priming in embryonic stem cells. Therefore, our results suggest complex interconnections between BRD2 and BRD3 at promoters to fine-tune Pol II initiation and elongation for control of cell state.
Collapse
Affiliation(s)
- Chenlu Wang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
| | - Qiqin Xu
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
| | - Xianhong Zhang
- Hubei Key Laboratory of Cell Homeostasis, RNA Institute, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Daniel S Day
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA, 02142, USA
| | - Brian J Abraham
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA, 02142, USA
- Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, TN, 38105, USA
| | - Kehuan Lun
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
| | - Liang Chen
- Hubei Key Laboratory of Cell Homeostasis, RNA Institute, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Jie Huang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China.
| | - Xiong Ji
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China.
| |
Collapse
|