Characterization of a new SUMO-1 nuclear body (SNB) enriched in pCREB, CBP, c-Jun in neuron-like UR61 cells

TY - JOUR

T1 - Characterization of a new SUMO-1 nuclear body (SNB) enriched in pCREB, CBP, c-Jun in neuron-like UR61 cells

AU - Navascues, Joaquin

AU - Bengoechea, Rocio

AU - Tapia, Olga

AU - Vaqué, José P

AU - Lafarga, Miguel

AU - Berciano, Maria T

PY - 2007

Y1 - 2007

N2 - The neuron-like UR61 cell is a stable PC12 subline that contains a mouse N-ras oncogene. Dexamethasone (Dex) treatment induces a neuron-like differentiation, which is associated with neuritogenesis and nuclear expression of the glucocorticoid receptor and c-Jun. In differentiated UR61 cells, small ubiquitin-like modifiers 1 (SUMO-1) is concentrated in a new category of SUMO-1 nuclear bodies (SNBs) distinct from promyelocytic leukemia (PML) bodies by their large size and absence of PML protein. SNBs are 1 to 3 mum in diameter and exhibit a fine granular texture by electron microscopy. They are free of splicing factors and transcription foci and show spatial associations with Cajal bodies. In addition to SUMO-1 and the E2-conjugating enzyme Ubc9, which is essential for sumoylation, SNBs concentrate the transcriptional regulators CBP, CREB, and c-Jun. Moreover, transfection experiments demonstrate that SNBs accumulate the active conjugating form of SUMO-1 but not the conjugation defective variant of SUMO-1, supporting that SNBs are sites of sumoylation. Our results suggest that SNBs play a role in the control of the nucleoplasmic concentration of transcription regulators involved in neuroprotection and survival of the UR61 cells.

AB - The neuron-like UR61 cell is a stable PC12 subline that contains a mouse N-ras oncogene. Dexamethasone (Dex) treatment induces a neuron-like differentiation, which is associated with neuritogenesis and nuclear expression of the glucocorticoid receptor and c-Jun. In differentiated UR61 cells, small ubiquitin-like modifiers 1 (SUMO-1) is concentrated in a new category of SUMO-1 nuclear bodies (SNBs) distinct from promyelocytic leukemia (PML) bodies by their large size and absence of PML protein. SNBs are 1 to 3 mum in diameter and exhibit a fine granular texture by electron microscopy. They are free of splicing factors and transcription foci and show spatial associations with Cajal bodies. In addition to SUMO-1 and the E2-conjugating enzyme Ubc9, which is essential for sumoylation, SNBs concentrate the transcriptional regulators CBP, CREB, and c-Jun. Moreover, transfection experiments demonstrate that SNBs accumulate the active conjugating form of SUMO-1 but not the conjugation defective variant of SUMO-1, supporting that SNBs are sites of sumoylation. Our results suggest that SNBs play a role in the control of the nucleoplasmic concentration of transcription regulators involved in neuroprotection and survival of the UR61 cells.

KW - Animals

KW - CREB-Binding Protein

KW - Cell Nucleolus

KW - Cells, Cultured

KW - Dexamethasone

KW - Gene Expression Regulation

KW - JNK Mitogen-Activated Protein Kinases

KW - Neurons

KW - PC12 Cells

KW - Rats

KW - SUMO-1 Protein

U2 - 10.1007/s00412-007-0107-7

DO - 10.1007/s00412-007-0107-7

M3 - Article

C2 - 17549507

SN - 0009-5915

VL - 116

SP - 441

EP - 451

JO - Chromosoma

JF - Chromosoma

IS - 5

ER -