A diverse antibody repertoire in B cells is generated through the various processes such as V(D)J rearrangement, class switching recombination, and somatic hypermutation at the immunoglobulin(Ig) gene loci. During early B cell development, these Ig genes are initially assembled into functional transcription units by V(D)J rearrangement, a fundamental mechanism for antibody diversity. Several lymphoid-specific factors are recognized to be involved in these recombination processes which can facilitate long-distance interaction of Ig gene segments in germ-line DNA. Proteins within the nucleocytoplasmic compartment are dynamically modified by the addition of O-linked β-N-acetylglucosamine (O-GlcNAc), derived from the end-product uridine 5’-phosphate (UDP)-GlcNAc of the hexosamine biosynthetic pathway (HBP), to serine and threonine hydroxyl groups. Modifications by O-GlcNAcylation can modulate a protein function by altering stability, subcellular localization, protein–protein interaction, phosphorylation status and/or DNA binding ability. Despite the essential role of O-GlcNAcylation in regulating protein function, the linked mechanisms of O-GlcNAcylation and V(D)J recombination remain largely unknown. Here, we show that the long-range interaction in Ig gene loci spanning >3MB is defective during V(D)J recombination in B cells from bone marrow of mice administered with O-GlcNAc inhibitors. Restricted V(D)J recombination is similarly confirmed in a mouse model with nutritional deficiency induced by limiting calorie consumption to 50%. However, defected rearrangement is restored by applying the O-GlcNAc-inducible drugs even during caloric restriction. Significantly, several factors involved in V(D)J recombination such as YY1, SMC1, and SMC3, which can regulate long-range interactions by binding to various positions in the Ig gene loci, are identified as proteins directly modified by O-GlcNAcylation. In addition, DNA binding ability of these proteins is shown to be disrupted once O-GlcNAcylation is inhibited. These results unravel a previously unidentified link between O-GlcNAcylation and V(D)J rearrangement and potentially suggests a crucial role for O-GlcNAc signaling in representing nutritional state to affect antibody diversity.
저자
Bong Chan Jeon [ Immunotherapy Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology(KRIBB), Daejeon 34141, Republic of Korea ]
Junghyun Lim [ School of Pharmacy, Jeonbuk National University, Jeonju 54896, Republic of Korea ]
Sung-Kyun Park [ Infectious Disease Research Center, Korea Research Institute of Bioscience and Biotechnology(KRIBB), Daejeon 34141, Republic of Korea ]
Corresponding Author
본 학회는 화학, 생화학, 분자생물학, 미생물학, 식품공학, 의학, 약학, 유전공학 및 생물공학, 환경 및 기타 공업 등 전 분야의 탄수화물관련 이론과 기술을 연구 발전시키고 산학협동을 통해 이를 보급하여 국내 관련 산업의 발전 및 국민생활의 과학화에 기여하고자 하며, 이러한 목표와 비젼의 실현을 위해 회원들이 적극적인 참여와 활동을 전개하고자 한다.