TY  - JOUR
A1  - Gehmlich, Katja
A1  - Geier, C.
A1  - Osterziel, Karl Joseph
A1  - Fürst, Dieter Oswald
T1  - Mutant muscle LIM protein is associated with hypertrophic cardiomyopathy and exhibits altered binding properties in the system MLP - N-RAP - alpha-actinin
Y1  - 2004
SN  - 0171-9335
ER  - 
TY  - JOUR
A1  - Gehmlich, Katja
A1  - Geier, C.
A1  - Osterziel, Karl Joseph
A1  - VanderVen, Peter F. M.
A1  - Fürst, Dieter Oswald
T1  - Decreased interactions of mutant muscle LIM protein (MLP) with N-RAP and alpha-actinin and their implication for hypertrophic cardiomyopathy
N2  - Previous work has shown that mutations in muscle LIM protein (MLP) can cause hypertrophic cardiomyopathy (HCM). In order to gain an insight into the molecular basis of the disease phenotype, we analysed the binding characteristics of wild-type MLP and of the (C58G) mutant MLP that causes hypertrophic cardiomyopathy. We show that MLP can form a ternary complex with two of its previously documented myofibrillar ligand proteins, N-RAP and alpha-actinin, which indicates the presence of distinct, non-overlapping binding sites. Our data also show that, in comparison to wild-type MLP, the capacity of the mutated MLP protein to bind both N-RAP and alpha-actinin is significantly decreased. In addition, this single point mutation prevents zinc coordination and proper folding of the second zinc-finger in the first LIM domain, which consequently renders the protein less stable and more susceptible to proteolysis. The molecular basis for HCM-causing mutations in the MLP gene might therefore be an alteration in the equilibrium of interactions of the ternary complex MLP-N-RAP-alpha-actinin. This assumption is supported by the previous observation that in the pathological situation accompanied by MLP down regulation, cardiomyocytes try to compensate for the decreased stability of MLP protein by increasing the expression of its ligand N-RAP, which might finally result in the development of myocyte disarray that is characteristic of this disease
Y1  - 2004
SN  - 0302-766X
ER  - 
TY  - JOUR
A1  - Kupfer, Thomas
A1  - Bauer, Evan B.
A1  - van Roestel, Jan
A1  - Bellm, Eric C.
A1  - Bildsten, Lars
A1  - Fuller, Jim
A1  - Prince, Thomas A.
A1  - Heber, Ulrich
A1  - Geier, Stephan
A1  - Green, Matthew J.
A1  - Kulkarni, Shrinivas R.
A1  - Bloemen, Steven
A1  - Laher, Russ R.
A1  - Rusholme, Ben
A1  - Schneider, David
T1  - Discovery of a Double-detonation Thermonuclear Supernova Progenitor
JF  - The astrophysical journal : an international review of spectroscopy and astronomical physics ; Part 2, Letters
N2  - We present the discovery of a new double-detonation progenitor system consisting of a hot subdwarf B (sdB) binary with a white dwarf companion with a P (orb) = 76.34179(2) minutes orbital period. Spectroscopic observations are consistent with an sdB star during helium core burning residing on the extreme horizontal branch. Chimera light curves are dominated by ellipsoidal deformation of the sdB star and a weak eclipse of the companion white dwarf. Combining spectroscopic and light curve fits, we find a low-mass sdB star, M (sdB) = 0.383 +/- 0.028 M (circle dot) with a massive white dwarf companion, M (WD) = 0.725 +/- 0.026 M (circle dot). From the eclipses we find a blackbody temperature for the white dwarf of 26,800 K resulting in a cooling age of approximate to 25 Myr whereas our MESA model predicts an sdB age of approximate to 170 Myr. We conclude that the sdB formed first through stable mass transfer followed by a common envelope which led to the formation of the white dwarf companion approximate to 25 Myr ago. Using the MESA stellar evolutionary code we find that the sdB star will start mass transfer in approximate to 6 Myr and in approximate to 60 Myr the white dwarf will reach a total mass of 0.92 M (circle dot) with a thick helium layer of 0.17 M (circle dot). This will lead to a detonation that will likely destroy the white dwarf in a peculiar thermonuclear supernova. PTF1 J2238+7430 is only the second confirmed candidate for a double-detonation thermonuclear supernova. Using both systems we estimate that at least approximate to 1% of white dwarf thermonuclear supernovae originate from sdB+WD binaries with thick helium layers, consistent with the small number of observed peculiar thermonuclear explosions.
Y1  - 2022
U6  - https://doi.org/10.3847/2041-8213/ac48f1
SN  - 2041-8205
SN  - 2041-8213
VL  - 925
IS  - 2
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  -