The L266V tau mutation is associated with frontotemporal dementia and Pick-like 3R and 4R tauopathy.
We report a case of rapidly progressive frontotemporal dementia presenting at age 33 years. At autopsy there was severe atrophy of the frontal and temporal lobes. Tau-positive Pick bodies, which ultrastructurally were composed of straight filaments, were present, accompanied by severe neuronal loss and gliosis. RD3, a tau antibody specific for the three-repeat (3R) isoforms, labeled the Pick bodies. ET3, a four-repeat (4R) isoform-specific tau antibody, did not label Pick bodies, but highlighted rare astrocytes, and threads in white matter bundles in the corpus striatum. Analysis of the tau gene revealed an L266V mutation in exon 9. Analysis of brain tissue from this case revealed elevated levels of exon 10+ tau RNA and soluble 4R tau. However, both 3R and 4R isoforms were present in sarkosyl-insoluble tau fractions with a predominance of the shortest 3R isoform. The L266V mutation is associated with decreased rate and extent of tau-induced microtubule assembly, and a 3R isoform-specific increase in tau self assembly as measured by an in vitro assay. Combined, these data indicate that L266V is a pathogenic tau mutation that is associated with Pick-like pathology. In addition, the results of the RD3 and ET3 immunostains clearly explain for the first time the presence of both 3R and 4R tau isoforms in preparations of insoluble tau from some Pick's disease cases.
Hogg
Marion
M
Neurogenetics Laboratory, Mayo Clinic Jacksonville, Jacksonville, Florida, USA.
Grujic
Zoran M
ZM
Baker
Matt
M
Demirci
Serpil
S
Guillozet
Angela L
AL
Sweet
Alison P
AP
Herzog
Laura L
LL
Weintraub
Sandra
S
Mesulam
M-Marsel
MM
LaPointe
Nichole E
NE
Gamblin
T C
TC
Berry
Robert W
RW
Binder
Lester I
LI
de Silva
Rohan
R
Lees
Andrew
A
Espinoza
Marisol
M
Davies
Peter
P
Grover
Andrew
A
Sahara
Naruhiko
N
Ishizawa
Takashi
T
Dickson
Dennis
D
Yen
Shu-Hui
SH
Hutton
Michael
M
Bigio
Eileen H
EH
D000328:Adult; D000911:Antibodies, Monoclonal / Q000378:metabolism; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D004252:DNA Mutational Analysis; D003704:Dementia / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D005091:Exons; D005192:Family Health; D006801:Humans; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D007930:Leucine / Q000235:genetics; D008297:Male; D008854:Microscopy, Electron; D008870:Microtubules / Q000187:drug effects / Q000378:metabolism; D009154:Mutation; D020774:Pick Disease of the Brain / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D020033:Protein Isoforms / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis; D017466:Receptors, Endothelin / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D024801:Tauopathies / Q000235:genetics* / Q000378:metabolism; D013997:Time Factors; D014633:Valine / Q000235:genetics; D016875:tau Proteins / Q000235:genetics* / Q000378:metabolism
D000911:Antibodies, Monoclonal; C085349:PHF-1 monoclonal antibody; D020033:Protein Isoforms; D012333:RNA, Messenger; D017466:Receptors, Endothelin; C098996:endothelin-3 receptor; D016875:tau Proteins; D007930:Leucine; D014633:Valine