The sequence and secondary structure of the 5'-end of mRNAs regulate translation by controlling ribosome initiation on the mRNA. Ribosomal protein S1 is crucial for ribosome initiation on many natural mRNAs, particularly for those with structured 5'-ends, or with no or weak Shine-Dalgarno sequences. Besides a critical role in translation, S1 has been implicated in several other cellular process...

Despite of the high resolution structure available for the E. coli ribosome, hitherto the structure and localization of the essential ribosomal protein S1 on the 30 S subunit still remains to be elucidated. It was previously reported that protein S1 binds to the ribosome via protein-protein interaction at the two N-terminal domains. Moreover, protein S2 was shown to be required for binding of p...

We consider QCD-like theories with one massless fermion in various representations of the gauge group SU(N). The theories are formulated on R3 ×S1. In the decompactification limit of large r(S1) all these theories are characterized by confinement, mass gap and spontaneous breaking of a (discrete) chiral symmetry (χSB). At small r(S1), in order to stabilize the vacua of these theories at a cente...

We consider QCD-like theories with one massless fermion in various representations of the gauge group SU(N). The theories are formulated on R3×S1. In the decompactification limit of large r(S1) all these theories are characterized by confinement, mass gap and spontaneous breaking of a (discrete) chiral symmetry (χSB). At small r(S1), in order to stabilize the vacua of these theories at a center...

Myosin head (myosin subfragment 1, S1) consists of two major structural domains, the motor (or catalytic) domain and the regulatory domain. Functioning of the myosin head as a molecular motor is believed to involve a rotation of the regulatory domain (lever arm) relative to the motor domain during the ATPase cycle. According to predictions, this rotation can be accompanied by an interaction bet...

Equilibrium measurements of the rate of binding of caldesmon and myosin S1 to actin-tropomyosin from different laboratories have yielded different results and have led to different models of caldesmon function. An alternate approach to answering these questions is to study the kinetics of binding of both caldesmon and S1 to actin. We observed that caldesmon decreased the rate of binding of S1 t...

We show that negative-stain electron microscopy and image processing of nucleotide-free (apo) striated muscle myosin-2 subfragment-1 (S1), possessing one light chain or both light chains, is capable of resolving significant amounts of structural detail. The overall appearance of the motor and the lever is similar in rabbit, scallop and chicken S1. Projection matching of class averages of the di...

Ribosomal protein S1 is known to play an important role in translational initiation, being directly involved in recognition and binding of mRNAs by 30S ribosomal particles. Using a specially developed procedure based on efficient crosslinking of S1 to mRNA induced by UV irradiation, we have identified S1 binding sites on several phage RNAs in preinitiation complexes. Targets for S1 on Q beta an...

Imaging using affibody molecules enables discrimination between breast cancer metastases with high and low expression of HER2, making appropriate therapy selection possible. This study aimed to evaluate if the longer half-life of 64Cu (T1/2 = 12.7 h) would make 64Cu a superior nuclide compared to 68Ga for PET imaging of HER2 expression using affibody molecules. The synthetic ZHER2:S1 affibody m...

We compared the thermal aggregation properties of two isoforms of the isolated myosin head (myosin subfragment 1, S1) containing different "essential" (or "alkali") light chains, A1 or A2. Temperature dependencies for the aggregation of these two S1 isoforms, as measured by the increase in turbidity, were compared with the temperature dependencies of their thermal denaturation obtained from dif...