In the healthy brain, less than 5% of α-synuclein (α-syn) is phosphorylated at serine 129 (Ser(P)-129). However, within Parkinson disease (PD) Lewy bodies, 89% of α-syn is Ser(P)-129. The effects of Ser(P)-129 modification on α-syn distribution and solubility are poorly understood. As α-syn normally exists in both membrane-bound and cytosolic compartments, we examined the binding and dissociati...

The amino acid sequences of both the alpha and beta subunits of human chorionic gonadotropin have been determined. The amino acid sequence of the alpha subunit is: Ala - Asp - Val - Gln - Asp - Cys - Pro - Glu - Cys-10 - Thr - Leu - Gln - Asp - Pro - Phe - Ser - Gln-20 - Pro - Gly - Ala - Pro - Ile - Leu - Gln - Cys - Met - Gly-30 - Cys - Cys - Phe - Ser - Arg - Ala - Tyr - Pro - Thr - Pro-40 -...

N-linked glycosylation can profoundly affect protein expression and function. N-linked glycosylation usually occurs at the sequon Asn-Xaa-Ser/Thr, where Xaa is any amino acid residue except Pro. However, many Asn-Xaa-Ser/Thr sequons are glycosylated inefficiently or not at all for reasons that are poorly understood. We have used a site-directed mutagenesis approach to examine how the Xaa and hy...

Troponin I (TnI) is a major regulator of cardiac muscle contraction and relaxation. During physiological and pathological stress, TnI is differentially phosphorylated at multiple residues through different signaling pathways to match cardiac function to demand. The combination of these TnI phosphorylations can exhibit an expected or unexpected functional integration, whereby the function of two...

Choline acetyltransferase (ChAT) synthesizes acetylcholine in cholinergic neurons; regulation of its activity or response to physiological stimuli is poorly understood. We show that ChAT is differentially phosphorylated by protein kinase C (PKC) isoforms on four serines (Ser-440, Ser-346, Ser-347, and Ser-476) and one threonine (Thr-255). This phosphorylation is hierarchical, with phosphorylati...

Wide band code division multiple access (WCDMA) signals, transmitted by the base station high power amplifiers (HPAs), show high peak to average power ratios (PAPR), which results in nonlinear distortions. In this paper, using computer simulations effect of using a predistorted HPA on the symbol error rate (SER) of multi-user detectors in terms of output back-off (OBO) in the transmit power...

RATIONALE Cardiac myosin-binding protein-C (cMyBP-C) phosphorylation at Ser-273, Ser-282, and Ser-302 regulates myocardial contractility. In vitro and in vivo experiments suggest the nonequivalence of these sites and the potential importance of Ser-282 phosphorylation in modulating the protein's overall phosphorylation and myocardial function. OBJECTIVE To determine whether complete cMyBP-C p...

Selenocysteine (Sec) biosynthesis in archaea and eukaryotes requires three steps: serylation of tRNA(Sec) by seryl-tRNA synthetase (SerRS), phosphorylation of Ser-tRNA(Sec) by O-phosphoseryl-tRNA(Sec) kinase (PSTK), and conversion of O-phosphoseryl-tRNA(Sec) (Sep-tRNA(Sec)) by Sep-tRNA:Sec-tRNA synthase (SepSecS) to Sec-tRNA(Sec). Although SerRS recognizes both tRNA(Sec) and tRNA(Ser) species, ...

To initiate fertilization, mouse sperm bind to Ser- (O-) linked oligosaccharides located at the sperm combining site of zona pellucida glycoprotein mZP3. Apparently, the oligosaccharides are present on one or more of five Ser residues clustered in the carboxyl-terminal region of the mZP3 polypeptide. Here, each of the Ser residues, as well as an intervening Asn residue, was converted to a small...