4 research outputs found
A novel lipid binding protein is a factor required for MgATP stimulation of the squid nerve Na+/Ca2+ exchanger
Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Biochimica et Biophysica Acta - Biomembranes 1788 (2009): 1255-1262, doi:10.1016/j.bbamem.2008.12.016.Here we identify a cytosolic factor essential for MgATP up-regulation of the squid nerve
Na+/Ca2+ exchanger. Mass spectroscopy and Western blot analysis established that this
factor is a member of the lipocalin super family of lipid binding proteins of 132 amino
acids in length. We named it Regulatory protein of the squid nerve sodium calcium
exchanger (ReP1-NCXSQ). ReP-1-NCXSQ was cloned, over expressed and purified. Far-
UV circular dichroism and infrared spectra suggest a majority of β-strand in the secondary
structure. Moreover, the predicted tertiary structure indicates ten β-sheets and two short α-
helices characteristic of most lipid binding proteins. Functional experiments showed that in
order to be active ReP1-NCXSQ must become phosphorylated in the presence of MgATP
by a kinase that is Staurosporin insensitive. Even more, the phosphorylated ReP1-NCXSQ
is able to stimulate the exchanger in the absence of ATP. In addition to the identification of
a new member of the lipid binding protein family, this work shows, for the first time, the
requirement of a lipid binding protein for metabolic regulation of an ion transporting
system.The work was supported by Grants from the US National Science Foundation [MCB
0444598], Fondo Nacional para Investigaciones CientĂficas y TecnolĂłgicas [PICT-05-
12397 and PICT-05-38073], Consejo Nacional de Investigfaciones CientĂficas y TĂ©cnicas
[PIP 5118 and PIP 5593] SecretarĂa de Ciencia y TĂ©cnica Universidad Nacional de
CĂłrdoba, Argentina, Fondo Nacional para Ciencia y TĂ©cnica [S1-9900009046 and G-
2001000637] and FundaciĂłn Polar, Venezuela and The Rhode Island Idea Network of
Biomedical Research Excellence (INBRE)
Trump Demanded \u27Loyalty\u27 and Asked for an End to the Flynn Investigation, Comey will Testify
[quote] “If Comey is right — and the president was asking him to drop the investigation — we have an increasingly strong case of obstruction,” Jennifer Daskal, a law professor at American University, said Wednesday.
“After all, if a president asking his top law enforcement official to halt an investigation isn’t an effort to impede, I don’t what is.
Trump Demanded \u27Loyalty\u27 and Asked for an End to the Flynn Investigation, Comey will Testify
[quote] “If Comey is right — and the president was asking him to drop the investigation — we have an increasingly strong case of obstruction,” Jennifer Daskal, a law professor at American University, said Wednesday.
“After all, if a president asking his top law enforcement official to halt an investigation isn’t an effort to impede, I don’t what is.