Expansion of the human mitochondrial proteome by intra- and inter-compartmental protein duplication

The human mitochondrial proteome is shown to have expanded due to duplication of protein encoding genes and re-localization of these duplicated proteins

A 3-D differential surface admittance operator for lossy dipole antenna analysis

This letter presents a novel approach to simulate materials with arbitrary properties, in particular good conductors, in a boundary integral equation context. The advocated differential surface admittance operator permits the replacement of the material by the background medium through the introduction of an equivalent surface current density. A formulation based on the eigenfunctions of the volume is constructed and successfully demonstrated through scattering at a conducting cylinder and through the analysis of a lossy dipole antenna

An enhanced differential surface admittance operator for the signal integrity modeling of interconnects

A new, enhanced formulation of the 3-D differential surface admittance operator is presented in this contribution. By employing closed expressions for the sums of the infinite series that arise from discretizing the operator by means of entire domain basis functions, a more efficient and accurate form is obtained. Convergence analysis demonstrates the performance gain. Additionally, the appositeness of the novel operator is studied by analyzing results for various interconnect structures over a broad frequency range and by comparing with other research and commercial solvers

From Endosymbiont to Host-Controlled Organelle: The Hijacking of Mitochondrial Protein Synthesis and Metabolism

Mitochondria are eukaryotic organelles that originated from the endosymbiosis of an alpha-proteobacterium. To gain insight into the evolution of the mitochondrial proteome as it proceeded through the transition from a free-living cell to a specialized organelle, we compared a reconstructed ancestral proteome of the mitochondrion with the proteomes of alpha-proteobacteria as well as with the mitochondrial proteomes in yeast and man. Overall, there has been a large turnover of the mitochondrial proteome during the evolution of mitochondria. Early in the evolution of the mitochondrion, proteins involved in cell envelope synthesis have virtually disappeared, whereas proteins involved in replication, transcription, cell division, transport, regulation, and signal transduction have been replaced by eukaryotic proteins. More than half of what remains from the mitochondrial ancestor in modern mitochondria corresponds to translation, including post-translational modifications, and to metabolic pathways that are directly, or indirectly, involved in energy conversion. Altogether, the results indicate that the eukaryotic host has hijacked the proto-mitochondrion, taking control of its protein synthesis and metabolism

Complex fate of paralogs

<p>Abstract</p> <p>Background</p> <p>Thanks to recent high coverage mass-spectrometry studies and reconstructed protein complexes, we are now in an unprecedented position to study the evolution of biological systems. Gene duplications, known to be a major source of innovation in evolution, can now be readily examined in the context of protein complexes.</p> <p>Results</p> <p>We observe that paralogs operating in the same complex fulfill different roles: mRNA dosage increase for more than a hundred cytosolic ribosomal proteins, mutually exclusive participation of at least 54 paralogs resulting in alternative forms of complexes, and 24 proteins contributing to <it>bona fide </it>structural growth. Inspection of paralogous proteins participating in two independent complexes shows that an ancient, pre-duplication protein functioned in both multi-protein assemblies and a gene duplication event allowed the respective copies to specialize and split their roles.</p> <p>Conclusion</p> <p>Variants with conditionally assembled, paralogous subunits likely have played a role in yeast's adaptation to anaerobic conditions. In a number of cases the gene duplication has given rise to one duplicate that is no longer part of a protein complex and shows an accelerated rate of evolution. Such genes could provide the raw material for the evolution of new functions.</p

Broadband full-wave BIE impedance characterization of 3-D interconnects

In this paper, a full-wave boundary integral equation formulation is proposed that accurately characterizes 3-D interconnects. By extending a recently presented framework for the resistance and inductance calculation that employs a 3-D differential surface admittance operator, the total impedance is computed. The inclusion of capacitive effects is validated and demonstrated over a broad frequency range

EMC-aware analysis and design of a low-cost receiver circuit under injection locking and pulling

In low-cost receiver applications, the preselect filter is often omitted in order to reduce the footprint of the total system. However, the immunity of the receiver can be severely compromised by this approach. This paper focuses on the effects of co-located sources on the local oscillator (LO), specifically injection locking and pulling. To this end, a low-cost radio receiver (RF) front-end is designed for operation in the 2 : 4 5 GHz industrial, scientific and medical (ISM) radio band. In addition to the effects on the oscillator, the consequences on the receiver's performance are evaluated as well. For the first time in literature, this work demonstrates the critical necessity to take the potentially detrimental effects caused by injection locking and pulling into account during Electromagnetic Compatibility (EMC)-aware design

Rigorous full-wave resistance and inductance computation of 3-D interconnects

A full-wave technique to rigorously extract the resistance and the inductance of 3-D interconnects is proposed. A novel and full 3-D differential surface admittance operator and a boundary integral equation approach are combined in a circuit interpretation which provides a simple way to evaluate the characteristics of the interconnects. The method is accurate for various examples over a broad frequency range, thus conforming its appositeness for the modeling of 3-D interconnects