3 research outputs found
KINATEST-ID: A Pipeline To Develop Phosphorylation-Dependent Terbium Sensitizing Kinase Assays
Nonreceptor
protein tyrosine kinases (NRTKs) are essential for
cellular homeostasis and thus are a major focus of current drug discovery
efforts. Peptide substrates that can enhance lanthanide ion luminescence
upon tyrosine phosphorylation enable rapid, sensitive screening of
kinase activity, however design of suitable substrates that can distinguish
between tyrosine kinase families is a huge challenge. Despite their
different substrate preferences, many NRTKs are structurally similar
even between families. Furthermore, the development of lanthanide-based
kinase assays is hampered by incomplete understanding of how to integrate
sequence selectivity with metal ion binding, necessitating laborious
iterative substrate optimization. We used curated proteomic data from
endogenous kinase substrates and known Tb<sup>3+</sup>-binding sequences
to build a generalizable <i>in silico</i> pipeline with
tools to generate, screen, align, and select potential phosphorylation-dependent
Tb<sup>3+</sup>-sensitizing substrates that are most likely to be
kinase specific. We demonstrated the approach by developing several
substrates that are selective within kinase families and amenable
to high-throughput screening (HTS) applications. Overall, this strategy
represents a pipeline for developing efficient and specific assays
for virtually any tyrosine kinase that use HTS-compatible lanthanide-based
detection. The tools provided in the pipeline also have the potential
to be adapted to identify peptides for other purposes, including other
enzyme assays or protein-binding ligands
Super-adiabatic temperature gradient at Jupiter's equatorial zone and implications for the water abundance
The temperature structure of a giant planet was traditionally thought to be an adiabat assuming convective mixing homogenizes entropy. The only in-situ measurement made by the Galileo Probe detected a near-adiabatic temperature structure within one of Jupiter's 5μm hot spots with small but definite local departures from adiabaticity. We analyze Juno's microwave observations near Jupiter's equator (0– 5 oN) and find that the equatorial temperature structure is best characterized by a stable super-adiabatic temperature profile rather than an adiabatic one. Water is the only substance with sufficient abundance to alter the atmosphere's mean molecular weight and prevent dynamic instability if a super-adiabatic temperature gradient exists. Thus, from the super-adiabaticity, our results indicate a water concentration (or the oxygen to hydrogen ratio) of about 4.9 times solar with a possible range of 1.5– 8.3 times solar in Jupiter's equatorial region
Residual Study: Testing Jupiter Atmosphere Models Against Juno MWR Observations
The Juno spacecraft provides unique close‐up views of Jupiter underneath the synchrotron radiation belts while circling Jupiter in its 53‐day orbits. The microwave radiometer (MWR) onboard measures Jupiter thermal radiation at wavelengths between 1.37 and 50 cm, penetrating the atmosphere to a pressure of a few hundred bars and greater. The mission provides the first measurements of Jupiter's deep atmosphere, down to ~250 bars in pressure, constraining the vertical distributions of its kinetic temperature and constituents. As a result, vertical structure models of Jupiter's atmosphere may now be tested by comparison with MWR data. Taking into account the MWR beam patterns and observation geometries, we test several published Jupiter atmospheric models against MWR data. Our residual analysis confirms Li et al.'s (2017, https://doi.org/10.1002/2017GL073159) result that ammonia depletion persists down to 50–60 bars where ground‐based Very Large Array was not able to observe. We also present an extension of the study that iteratively improves the input model and generates Jupiter brightness temperature maps which best match the MWR data. A feature of Juno's north‐to‐south scanning approach is that latitudinal structure is more easily obtained than longitudinal, and the creation of optimum two‐dimensional maps is addressed in this approach