[Study on aggregate formation mechanism of HSPB8 gene mutation resulting in CMT2L].
OBJECTIVE
To study the possible mechanism of the intracellular aggregate formation of small heat shock protein HSPB8 (HSPB8)(K141N) mutation resulting in axonal Charcot-Marie-Tooth disease type 2L(CMT2L).


METHODS
The cell models which transiently expressed pEGFPN1-HSPB8 and pEGFPN1-(K141N)HSPB8 were established. The immunofluorescent co-location study of EGFP-(K141N)HSPB8 and HSPB1, EGFP-(K141N)HSPB8 and neurofilament light chain (NEFL) was carried out in the SHSY5Y cell models. The aggregate formation of EGFP-(K141N)HSPB8 in cell models was investigated and the possible mechanism of cellular aggregate formation was analyzed by t test and analysis of variance between group(ANOVA).


RESULTS
EGFP-(K141N)HSPB8 formed large aggregate which predominantly located around the nucleus in cell models. EGFP-(K141N)HSPB8 co-localized perfectly with HSPB1 and NEFL in the SHSY5Y cell models. The aggregate formation was different in different cell types, there were fewer aggregates formed in an sHSPs deficient milieu than in HEK293T cells.


CONCLUSIONS
(K141N)HSPB8 formed aggregates predominantly locate around the nucleus in cells. (K141N)HSPB8 co-localizes perfectly with HSPB1 and NEFL. The aggregate formation may be due to (K141N)HSPB8 conformational change leading to self aggregation and its abnormal interaction with other sHSPs such as HSPB1.
Zhang
Ru-xu
RX
Department of Neurology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P. R. China.
Tang
Bei-sha
BS
Zi
Xiao-hong
XH
Xia
Kun
K
Pan
Qian
Q
Zhang
Fu-feng
FF
Li
Shu-jian
SJ
Zhao
Guo-hua
GH
Guo
Ke
K
D002460:Cell Line; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000378:metabolism; D002607:Charcot-Marie-Tooth Disease / Q000235:genetics* / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D055551:HSP27 Heat-Shock Proteins; D006367:HeLa Cells; D006360:Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D007668:Kidney / Q000166:cytology / Q000378:metabolism; D018613:Microscopy, Confocal; D018832:Molecular Chaperones; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism; D009447:Neuroblastoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D016900:Neurofilament Proteins / Q000235:genetics / Q000378:metabolism; D017354:Point Mutation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D014162:Transfection
D055551:HSP27 Heat-Shock Proteins; C057725:HSPB1 protein, human; C413214:HSPB8 protein, human; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones; D009363:Neoplasm Proteins; D016900:Neurofilament Proteins; D011993:Recombinant Fusion Proteins; C485184:enhanced green fluorescent protein; C044882:neurofilament protein L; D049452:Green Fluorescent Proteins; D017346:Protein Serine-Threonine Kinases