Rapid and deep-scale ubiquitylation profiling for biology and translational research

Protein ubiquitylation is involved in a plethora of cellular processes. While antibodies directed at ubiquitin remnants (K-ɛ-GG) have improved the ability to monitor ubiquitylation using mass spectrometry, methods for highly multiplexed measurement of ubiquitylation in tissues and primary cells using sub-milligram amounts of sample remains a challenge. Here, we present a highly sensitive, rapid and multiplexed protocol termed UbiFast for quantifying ~10,000 ubiquitylation sites from as little as 500 μg peptide per sample from cells or tissue in a TMT10plex in ca. 5 h. High-field Asymmetric Waveform Ion Mobility Spectrometry (FAIMS) is used to improve quantitative accuracy for posttranslational modification analysis. We use the approach to rediscover substrates of the E3 ligase targeting drug lenalidomide and to identify proteins modulated by ubiquitylation in models of basal and luminal human breast cancer. The sensitivity and speed of the UbiFast method makes it suitable for large-scale studies in primary tissue samples

Squark-, Slepton- and Neutralino-Chargino coannihilation effects in the low-energy effective MSSM

Within the low-energy effective Minimal Supersymmetric extension of the Standard Model (effMSSM) we calculate the neutralino relic density taking into account slepton-neutralino, squark-neutralino and neutralino/chargino- neutralino coannihilation channels. By including squark (stop and sbottom) coannihilation channels we extend our comparative study to all allowed coannihilations and obtain the general result that all of them give sizable contributions to the reduction of the neutralino relic density. Due to these coannihilation processes some models (mostly with large neutralino masses) enter into the cosmologically interesting region for relic density, but other models leave this region. Nevertheless, in general, the predictions for direct and indirect dark matter detection rates are not strongly affected by these coannihilation channels in the effMSSM.Comment: 14 pages, 10 figures, corrected and to be published in Phys. Rev.

Slepton and Neutralino/Chargino Coannihilations in MSSM

Within the low-energy effective Minimal Supersymmetric extension of Standard Model (effMSSM) we calculated the neutralino relic density taking into account slepton-neutralino and neutralino-chargino/neutralino coannihilation channels. We performed comparative study of these channels and obtained that both of them give sizable contributions to the reduction of the relic density. Due to these coannihilation processes some models (mostly with large neutralino masses) enter into the cosmologically interesting region for relic density, but other models leave this region. Nevertheless, in general, the predictions for direct and indirect dark matter detection rates are not strongly affected by these coannihilation channels in the effMSSM.Comment: 12 pages, 9 figures, revte

Probing CP Violation with the Deuteron Electric Dipole Moment

We present an analysis of the electric dipole moment (EDM) of the deuteron as induced by CP-violating operators of dimension 4, 5 and 6 including theta QCD, the EDMs and color EDMs of quarks, four-quark interactions and the Weinberg operator. We demonstrate that the precision goal of the EDM Collaboration's proposal to search for the deuteron EDM, (1-3)\times 10^{-27} e cm, will provide an improvement in sensitivity to these sources of one-two orders of magnitude relative to the existing bounds. We consider in detail the level to which CP-odd phases can be probed within the MSSM.Comment: 5 pages, 4 figures; precision estimates clarified, to appear in Phys. Rev.

Constrained Supersymmetric Flipped SU(5) GUT Phenomenology

We explore the phenomenology of the minimal supersymmetric flipped SU(5) GUT model (CFSU(5)), whose soft supersymmetry-breaking (SSB) mass parameters are constrained to be universal at some input scale, $M_{in}$, above the GUT scale, $M_{GUT}$. We analyze the parameter space of CFSU(5) assuming that the lightest supersymmetric particle (LSP) provides the cosmological cold dark matter, paying careful attention to the matching of parameters at the GUT scale. We first display some specific examples of the evolutions of the SSB parameters that exhibit some generic features. Specifically, we note that the relationship between the masses of the lightest neutralino and the lighter stau is sensitive to $M_{in}$, as is the relationship between the neutralino mass and the masses of the heavier Higgs bosons. For these reasons, prominent features in generic $(m_{1/2}, m_0)$ planes such as coannihilation strips and rapid-annihilation funnels are also sensitive to $M_{in}$, as we illustrate for several cases with tan(beta)=10 and 55. However, these features do not necessarily disappear at large $M_{in}$, unlike the case in the minimal conventional SU(5) GUT. Our results are relatively insensitive to neutrino masses.Comment: 23 pages, 8 figures; (v2) added explanations and corrected typos, version to appear in EPJ

Improved Effective Potential in Curved Spacetime and Quantum Matter - Higher Derivative Gravity Theory

\noindent{\large\bf Abstract.} We develop a general formalism to study the renormalization group (RG) improved effective potential for renormalizable gauge theories ---including matter-$R^2$-gravity--- in curved spacetime. The result is given up to quadratic terms in curvature, and one-loop effective potentials may be easiliy obtained from it. As an example, we consider scalar QED, where dimensional transmutation in curved space and the phase structure of the potential (in particular, curvature-induced phase trnasitions), are discussed. For scalar QED with higher-derivative quantum gravity (QG), we examine the influence of QG on dimensional transmutation and calculate QG corrections to the scalar-to-vector mass ratio. The phase structure of the RG-improved effective potential is also studied in this case, and the values of the induced Newton and cosmological coupling constants at the critical point are estimated. Stability of the running scalar coupling in the Yukawa theory with conformally invariant higher-derivative QG, and in the Standard Model with the same addition, is numerically analyzed. We show that, in these models, QG tends to make the scalar sector less unstable.Comment: 23 pages, Oct 17 199

What if Supersymmetry Breaking Unifies beyond the GUT Scale?

We study models in which soft supersymmetry-breaking parameters of the MSSM become universal at some unification scale, $M_{in}$, above the GUT scale, \mgut. We assume that the scalar masses and gaugino masses have common values, $m_0$ and $m_{1/2}$ respectively, at $M_{in}$. We use the renormalization-group equations of the minimal supersymmetric SU(5) GUT to evaluate their evolutions down to \mgut, studying their dependences on the unknown parameters of the SU(5) superpotential. After displaying some generic examples of the evolutions of the soft supersymmetry-breaking parameters, we discuss the effects on physical sparticle masses in some specific examples. We note, for example, that near-degeneracy between the lightest neutralino and the lighter stau is progressively disfavoured as $M_{in}$ increases. This has the consequence, as we show in $(m_{1/2}, m_0)$ planes for several different values of $\tan \beta$, that the stau coannihilation region shrinks as $M_{in}$ increases, and we delineate the regions of the $(M_{in}, \tan \beta)$ plane where it is absent altogether. Moreover, as $M_{in}$ increases, the focus-point region recedes to larger values of $m_0$ for any fixed $\tan \beta$ and $m_{1/2}$. We conclude that the regions of the $(m_{1/2}, m_0)$ plane that are commonly favoured in phenomenological analyses tend to disappear at large $M_{in}$.Comment: 24 pages with 11 eps figures; references added, some figures corrected, discussion extended and figure added; version to appear in EPJ

WMAP-Compliant Benchmark Surfaces for MSSM Higgs Bosons

We explore `benchmark surfaces' suitable for studying the phenomenology of Higgs bosons in the minimal supersymmetric extension of the Standard Model (MSSM), which are chosen so that the supersymmetric relic density is generally compatible with the range of cold dark matter density preferred by WMAP and other observations. These benchmark surfaces are specified assuming that gaugino masses m_{1/2}, soft trilinear supersymmetry-breaking parameters A_0 and the soft supersymmetry-breaking contributions m_0 to the squark and slepton masses are universal, but not those associated with the Higgs multiplets (the NUHM framework). The benchmark surfaces may be presented as M_A-tan_beta planes with fixed or systematically varying values of the other NUHM parameters, such as m_0, m_{1/2}, A_0 and the Higgs mixing parameter mu. We discuss the prospects for probing experimentally these benchmark surfaces at the Tevatron collider, the LHC, the ILC, in B physics and in direct dark-matter detection experiments. An Appendix documents developments in the FeynHiggs code that enable the user to explore for her/himself the WMAP-compliant benchmark surfaces.Comment: Minor corrections, references added. 43 pages, 10 figures. Version to appear in JHE

Relating the CMSSM and SUGRA models with GUT scale and Super-GUT scale Supersymmetry Breaking

While the constrained minimal supersymmetric standard model (CMSSM) with universal gaugino masses, m_{1/2}, scalar masses, m_0, and A-terms, A_0, defined at some high energy scale (usually taken to be the GUT scale) is motivated by general features of supergravity models, it does not carry all of the constraints imposed by minimal supergravity (mSUGRA). In particular, the CMSSM does not impose a relation between the trilinear and bilinear soft supersymmetry breaking terms, B_0 = A_0 - m_0, nor does it impose the relation between the soft scalar masses and the gravitino mass, m_0 = m_{3/2}. As a consequence, tan(\beta) is computed given values of the other CMSSM input parameters. By considering a Giudice-Masiero (GM) extension to mSUGRA, one can introduce new parameters to the K\"ahler potential which are associated with the Higgs sector and recover many of the standard CMSSM predictions. However, depending on the value of A_0, one may have a gravitino or a neutralino dark matter candidate. We also consider the consequences of imposing the universality conditions above the GUT scale. This GM extension provides a natural UV completion for the CMSSM.Comment: 16 pages, 11 figures; added erratum correcting several equations and results in Sec.2, Sec.3 and 4 remain unaffected and conclusions unchange

Colliders and Cosmology

Dark matter in variations of constrained minimal supersymmetric standard models will be discussed. Particular attention will be given to the comparison between accelerator and direct detection constraints.Comment: Submitted for the SUSY07 proceedings, 15 pages, LaTex, 26 eps figure