Готові списки джерел за темами / TIM23 complex

Добірка наукової літератури з теми "TIM23 complex"

Автор: Grafiati

Опубліковано: 6 вересня 2023

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Статті в журналах з теми "TIM23 complex"

Ryan, Kathleen R., Roxanne S. Leung, and Robert E. Jensen. "Characterization of the Mitochondrial Inner Membrane Translocase Complex: the Tim23p Hydrophobic Domain Interacts with Tim17p but Not with Other Tim23p Molecules." Molecular and Cellular Biology 18, no. 1 (January 1, 1998): 178–87. http://dx.doi.org/10.1128/mcb.18.1.178.

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ABSTRACT Tim23p is a mitochondrial inner membrane protein essential for the import of proteins from the cytosol. Tim23p contains an amino-terminal hydrophilic segment and a carboxyl-terminal hydrophobic domain (Tim23Cp). To study the functions and interactions of the two parts of Tim23p separately, we constructed tim23N, encoding only the hydrophilic region of Tim23p, and tim23C, encoding only the hydrophobic domain of Tim23p. Only the Tim23C protein is imported into mitochondria, indicating that the mitochondrial targeting information in Tim23p resides in its membrane spans or intervening loops. Tim23Cp, however, cannot substitute for full-length Tim23p, suggesting that the hydrophilic portion of Tim23p also performs an essential function in mitochondrial protein import. We found that overexpression of Tim23Cp is toxic to yeast cells that carry the tim23-1 mutation. Excess Tim23Cp causes Tim23-1p to disappear, leavingtim23-1 cells without a full-length version of the Tim23 protein. If Tim17p, another inner membrane import component, is overexpressed along with Tim23Cp, the toxicity of Tim23Cp is largely reversed and the Tim23-1 protein no longer disappears. In coimmunoprecipitations from solubilized mitochondria, Tim17p associates with the Tim23C protein. In addition, we show that Tim23p and Tim17p can be chemically cross-linked to each other in intact mitochondria. We conclude that the hydrophobic domain encoded by tim23Ctargets Tim23p to the mitochondria and mediates the direct interaction between Tim23p and Tim17p. In contrast, Tim23Cp cannot be coimmunoprecipitated with Tim23p, raising the possibility that the hydrophobic domain of Tim23p does not interact with other Tim23 molecules.

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Alder, Nathan N., Jennifer Sutherland, Ashley I. Buhring, Robert E. Jensen, and Arthur E. Johnson. "Quaternary Structure of the Mitochondrial TIM23 Complex Reveals Dynamic Association between Tim23p and Other Subunits." Molecular Biology of the Cell 19, no. 1 (January 2008): 159–70. http://dx.doi.org/10.1091/mbc.e07-07-0669.

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Tim23p is an essential channel-forming component of the multisubunit TIM23 complex of the mitochondrial inner membrane that mediates protein import. Radiolabeled Tim23p monocysteine mutants were imported in vitro, incorporated into functional TIM23 complexes, and subjected to chemical cross-linking. Three regions of proximity between Tim23p and other subunits of the TIM23 complex were identified: Tim17p and the first transmembrane segment of Tim23p; Tim50p and the C-terminal end of the Tim23p hydrophilic region; and the entire hydrophilic domains of Tim23p molecules. These regions of proximity reversibly change in response to changes in membrane potential across the inner membrane and also when a translocating substrate is trapped in the TIM23 complex. These structural changes reveal that the macromolecular arrangement within the TIM23 complex is dynamic and varies with the physiological state of the mitochondrion.

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Gebert, Michael, Sandra G. Schrempp, Carola S. Mehnert, Anna K. Heißwolf, Silke Oeljeklaus, Raffaele Ieva, Maria Bohnert, et al. "Mgr2 promotes coupling of the mitochondrial presequence translocase to partner complexes." Journal of Cell Biology 197, no. 5 (May 21, 2012): 595–604. http://dx.doi.org/10.1083/jcb.201110047.

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Many mitochondrial proteins are synthesized with N-terminal presequences in the cytosol. The presequence translocase of the inner mitochondrial membrane (TIM23) translocates preproteins into and across the membrane and associates with the matrix-localized import motor. The TIM23 complex consists of three core components and Tim21, which interacts with the translocase of the outer membrane (TOM) and the respiratory chain. We have identified a new subunit of the TIM23 complex, the inner membrane protein Mgr2. Mitochondria lacking Mgr2 were deficient in the Tim21-containing sorting form of the TIM23 complex. Mgr2 was required for binding of Tim21 to TIM23CORE, revealing a binding chain of TIM23CORE-Mgr2/Tim21–respiratory chain. Mgr2-deficient yeast cells were defective in growth at elevated temperature, and the mitochondria were impaired in TOM-TIM23 coupling and the import of presequence-carrying preproteins. We conclude that Mgr2 is a coupling factor of the presequence translocase crucial for cell growth at elevated temperature and for efficient protein import.

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Kerscher, Oliver, Jason Holder, Maithreyan Srinivasan, Roxanne S. Leung, and Robert E. Jensen. "The Tim54p–Tim22p Complex Mediates Insertion of Proteins into the Mitochondrial Inner Membrane." Journal of Cell Biology 139, no. 7 (December 29, 1997): 1663–75. http://dx.doi.org/10.1083/jcb.139.7.1663.

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We have identified a new protein, Tim54p, located in the yeast mitochondrial inner membrane. Tim54p is an essential import component, required for the insertion of at least two polytopic proteins into the inner membrane, but not for the translocation of precursors into the matrix. Several observations suggest that Tim54p and Tim22p are part of a protein complex in the inner membrane distinct from the previously characterized Tim23p-Tim17p complex. First, multiple copies of the TIM22 gene, but not TIM23 or TIM17, suppress the growth defect of a tim54-1 temperature-sensitive mutant. Second, Tim22p can be coprecipitated with Tim54p from detergent-solubilized mitochondria, but Tim54p and Tim22p do not interact with either Tim23p or Tim17p. Finally, the tim54-1 mutation destabilizes the Tim22 protein, but not Tim23p or Tim17p. Our results support the idea that the mitochondrial inner membrane carries two independent import complexes: one required for the translocation of proteins across the inner membrane (Tim23p–Tim17p), and the other required for the insertion of proteins into the inner membrane (Tim54p–Tim22p).

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Lohret, Timothy A., Robert E. Jensen, and Kathleen W. Kinnally. "Tim23, a Protein Import Component of the Mitochondrial Inner Membrane, Is Required for Normal Activity of the Multiple Conductance Channel, MCC." Journal of Cell Biology 137, no. 2 (April 21, 1997): 377–86. http://dx.doi.org/10.1083/jcb.137.2.377.

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We previously showed that the conductance of a mitochondrial inner membrane channel, called MCC, was specifically blocked by peptides corresponding to mitochondrial import signals. To determine if MCC plays a role in protein import, we examined the relationship between MCC and Tim23p, a component of the protein import complex of the mitochondrial inner membrane. We find that antibodies against Tim23p, previously shown to inhibit mitochondrial protein import, inhibit MCC activity. We also find that MCC activity is altered in mitochondria isolated from yeast carrying the tim23-1 mutation. In contrast to wild-type MCC, we find that the conductance of MCC from the tim23-1 mutant is not significantly blocked by mitochondrial presequence peptides. Tim23 antibodies and the tim23-1 mutation do not, however, alter the activity of PSC, a presequence-peptide sensitive channel in the mitochondrial outer membrane. Our results show that Tim23p is required for normal MCC activity and raise the possibility that precursors are translocated across the inner membrane through the pore of MCC.

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Yablonska, Svitlana, Vinitha Ganesan, Lisa M. Ferrando, JinHo Kim, Anna Pyzel, Oxana V. Baranova, Nicolas K. Khattar, et al. "Mutant huntingtin disrupts mitochondrial proteostasis by interacting with TIM23." Proceedings of the National Academy of Sciences 116, no. 33 (July 25, 2019): 16593–602. http://dx.doi.org/10.1073/pnas.1904101116.

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Mutant huntingtin (mHTT), the causative protein in Huntington’s disease (HD), associates with the translocase of mitochondrial inner membrane 23 (TIM23) complex, resulting in inhibition of synaptic mitochondrial protein import first detected in presymptomatic HD mice. The early timing of this event suggests that it is a relevant and direct pathophysiologic consequence of mHTT expression. We show that, of the 4 TIM23 complex proteins, mHTT specifically binds to the TIM23 subunit and that full-length wild-type huntingtin (wtHTT) and mHTT reside in the mitochondrial intermembrane space. We investigated differences in mitochondrial proteome between wtHTT and mHTT cells and found numerous proteomic disparities between mHTT and wtHTT mitochondria. We validated these data by quantitative immunoblotting in striatal cell lines and human HD brain tissue. The level of soluble matrix mitochondrial proteins imported through the TIM23 complex is lower in mHTT-expressing cell lines and brain tissues of HD patients compared with controls. In mHTT-expressing cell lines, membrane-bound TIM23-imported proteins have lower intramitochondrial levels, whereas inner membrane multispan proteins that are imported via the TIM22 pathway and proteins integrated into the outer membrane generally remain unchanged. In summary, we show that, in mitochondria, huntingtin is located in the intermembrane space, that mHTT binds with high-affinity to TIM23, and that mitochondria from mHTT-expressing cells and brain tissues of HD patients have reduced levels of nuclearly encoded proteins imported through TIM23. These data demonstrate the mechanism and biological significance of mHTT-mediated inhibition of mitochondrial protein import, a mechanism likely broadly relevant to other neurodegenerative diseases.

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Tamura, Yasushi, Yoshihiro Harada, Takuya Shiota, Koji Yamano, Kazuaki Watanabe, Mihoko Yokota, Hayashi Yamamoto, Hiromi Sesaki, and Toshiya Endo. "Tim23–Tim50 pair coordinates functions of translocators and motor proteins in mitochondrial protein import." Journal of Cell Biology 184, no. 1 (January 12, 2009): 129–41. http://dx.doi.org/10.1083/jcb.200808068.

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Mitochondrial protein traffic requires coordinated operation of protein translocator complexes in the mitochondrial membrane. The TIM23 complex translocates and inserts proteins into the mitochondrial inner membrane. Here we analyze the intermembrane space (IMS) domains of Tim23 and Tim50, which are essential subunits of the TIM23 complex, in these functions. We find that interactions of Tim23 and Tim50 in the IMS facilitate transfer of precursor proteins from the TOM40 complex, a general protein translocator in the outer membrane, to the TIM23 complex. Tim23–Tim50 interactions also facilitate a late step of protein translocation across the inner membrane by promoting motor functions of mitochondrial Hsp70 in the matrix. Therefore, the Tim23–Tim50 pair coordinates the actions of the TOM40 and TIM23 complexes together with motor proteins for mitochondrial protein import.

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Mokranjac, Dejana, Martin Sichting, Dušan Popov-Čeleketić, Koyeli Mapa, Lada Gevorkyan-Airapetov, Keren Zohary, Kai Hell, Abdussalam Azem, and Walter Neupert. "Role of Tim50 in the Transfer of Precursor Proteins from the Outer to the Inner Membrane of Mitochondria." Molecular Biology of the Cell 20, no. 5 (March 2009): 1400–1407. http://dx.doi.org/10.1091/mbc.e08-09-0934.

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Transport of essentially all matrix and a number of inner membrane proteins is governed, entirely or in part, by N-terminal presequences and requires a coordinated action of the translocases of outer and inner mitochondrial membranes (TOM and TIM23 complexes). Here, we have analyzed Tim50, a subunit of the TIM23 complex that is implicated in transfer of precursors from TOM to TIM23. Tim50 is recruited to the TIM23 complex via Tim23 in an interaction that is essentially independent of the rest of the translocase. We find Tim50 in close proximity to the intermembrane space side of the TOM complex where it recognizes both types of TIM23 substrates, those that are to be transported into the matrix and those destined to the inner membrane, suggesting that Tim50 recognizes presequences. This function of Tim50 depends on its association with TIM23. We conclude that the efficient transfer of precursors between TOM and TIM23 complexes requires the concerted action of Tim50 with Tim23.

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Davis, Alison J., Naresh B. Sepuri, Jason Holder, Arthur E. Johnson, and Robert E. Jensen. "Two Intermembrane Space Tim Complexes Interact with Different Domains of Tim23p during Its Import into Mitochondria." Journal of Cell Biology 150, no. 6 (September 18, 2000): 1271–82. http://dx.doi.org/10.1083/jcb.150.6.1271.

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Tim23p (translocase of the inner membrane) is an essential import component located in the mitochondrial inner membrane. To determine how the Tim23 protein itself is transported into mitochondria, we used chemical cross-linking to identify proteins adjacent to Tim23p during its biogenesis. In the absence of an inner membrane potential, Tim23p is translocated across the mitochondrial outer membrane, but not inserted into the inner membrane. At this intermediate stage, we find that Tim23p forms cross-linked products with two distinct protein complexes of the intermembrane space, Tim8p–Tim13p and Tim9p–Tim10p. Tim9p and Tim10p cross-link to the COOH-terminal domain of the Tim23 protein, which carries all of the targeting signals for Tim23p. Therefore, our results suggest that the Tim9p–Tim10p complex plays a key role in Tim23p import. In contrast, Tim8p and Tim13p cross-link to the hydrophilic NH2-terminal segment of Tim23p, which does not carry essential import information and, thus, the role of Tim8p–Tim13p is unclear. Tim23p contains two matrix-facing, positively charged loops that are essential for its insertion into the inner membrane. The positive charges are not required for interaction with the Tim9p–Tim10p complex, but are essential for cross-linking of Tim23p to components of the inner membrane insertion machinery, including Tim54p, Tim22p, and Tim12p.

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Callegari, Sylvie, Luis Daniel Cruz-Zaragoza, and Peter Rehling. "From TOM to the TIM23 complex – handing over of a precursor." Biological Chemistry 401, no. 6-7 (May 26, 2020): 709–21. http://dx.doi.org/10.1515/hsz-2020-0101.

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AbstractMitochondrial precursor proteins with amino-terminal presequences are imported via the presequence pathway, utilizing the TIM23 complex for inner membrane translocation. Initially, the precursors pass the outer membrane through the TOM complex and are handed over to the TIM23 complex where they are sorted into the inner membrane or translocated into the matrix. This handover process depends on the receptor proteins at the inner membrane, Tim50 and Tim23, which are critical for efficient import. In this review, we summarize key findings that shaped the current concepts of protein translocation along the presequence import pathway, with a particular focus on the precursor handover process from TOM to the TIM23 complex. In addition, we discuss functions of the human TIM23 pathway and the recently uncovered pathogenic mutations in TIM50.

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Більше джерел

Дисертації з теми "TIM23 complex"

Silva, Alinne Costa. "Aparato de importação de proteínas mitocondriais em Aspergillus fumigatus: caracterização fenotípica da deleção da menor subunidade do complexo TIM23." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/17/17131/tde-06062017-161751/.

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O câncer de ovário (OvCa) se destaca dentre as neoplasias ginecológicas por ser um dos mais letais e de difícil diagnóstico. O OvCa ocorre devido ao acúmulo de alterações celulares progressivas promovidas por mutações no genoma de uma célula que, consequentemente, alteram as complexas vias de regulação celular que respondem a fatores internos, como reprogramação genética, ou externos, como a resposta a fatores de crescimento, que juntamente com outras alterações moleculares favorecem a progressão e a metástase. Uma importante etapa da cascata metastática é a transição epitélio-mesenquimal (EMT), um processo bem orquestrado que resulta na perda do fenótipo epitelial e aquisição do fenótipo mesenquimal pelas células tumorais, que adquirem um caráter mais invasivo e migratório, além de se tornarem mais resistentes às drogas. A desregulação de fatores de transcrição como ZEB1, TWIST e SNAI1, vias de sinalização, microRNAs e fatores de crescimento incluindo EGF, TGF? e HGF podem desencadear a EMT. Após a eficiente indução da EMT com EGF na linhagem epitelial de adenocarcinoma de ovário humano Caov-3, foi realizada a análise proteômica quantitativa detalhada, baseada na análise de frações subcelulares enriquecidas em proteínas de membrana, citosol e núcleo, obtidas por centrifugação diferencial e subsequente fracionamento de proteínas por SDS-PAGE, a fim de compreender mais profundamente os mecanismos moleculares modulados pela EMT no OvCa. A partir da análise dos dados coletados em um sistema de espectrometria de massas de alta resolução acoplados a cromatografia líquida (LCMS/MS) e com o auxílio da bioinformática foram identificadas redes de interação proteína-proteína diferencialmente expressas, relacionadas principalmente com a regulação do ciclo celular e do metabolismo. A indução da EMT por EGF resultou na ativação de importantes vias de sinalização, tais como PI3K/Akt/mTOR e Ras/MAPK Erk, além da parada do ciclo celular na fase G1 regulada pelo aumento dos níveis de p21Waf1/Cip1, independentemente de p53, e diminuição de proteínas checkpoint. Através da proteômica dirigida, o monitoramento de reações múltiplas (MRM) revelou que, após a indução da EMT por EGF, o metabolismo das células Caov-3 foi alterado de uma maneira bastante peculiar. O estudo proteômico descrito permitiu a correlação entre processo da EMT induzido por EGF com o controle translacional, a regulação do ciclo celular e a alteração do metabolismo energético.
Ovarian cancer (OvCa) stands out among gynecological malignancies for being one of the most lethal and difficult to diagnose. OvCa occurs due to the accumulation of progressive cell changes promoted by mutations in the cell genome which, consequently, alter the complex cellular regulation pathways that respond to internal factors, such as genetic reprogramming, or external, such as response to growth factors, which together with other molecular changes favor the progression and metastasis. An important step of the metastatic cascade is the epithelial-mesenchymal transition (EMT), a well-orchestrated process that results in the loss of epithelial phenotype and acquisition of mesenchymal phenotype by tumor cells that acquire a more invasive and migratory character, and become more resistant to drugs. Deregulation of transcription factors such as ZEB1, TWIST and SNAI1, signaling pathways, microRNAs and growth factors including EGF, TGF? and HGF can trigger EMT. After an efficient EMT induction by EGF in the epithelial cell line of human adenocarcinoma ovarian Caov-3, detailed quantitative proteomic analysis was performed based on analysis of subcellular fractions enriched in proteins from membrane, cytosol and nucleus, obtained by differential centrifugation and subsequent fractionation of proteins by SDS-PAGE, in order to understand deeply the molecular mechanisms modulated by EMT in OvCa. From the analysis of data collected in a highresolution mass spectrometry system coupled to liquid chromatography (LC-MS/MS) and with the aid of bioinformatics were identified protein-protein interaction networks differentially expressed, mainly related to regulation cell cycle and metabolism. EGF induced-EMT resulted in the activation of major signaling pathways such as PI3K/Akt/mTOR and Ras/MAPK Erk, in addition to G1 phase cell cycle arrest regulated by increased levels of p21Waf1/Cip1, regardless of p53, and reduction of checkpoint proteins. Through the targeted proteomics, multiple reaction monitoring (MRM) showed that after EGF induced-EMT, Caov-3 cells metabolism was changed in a very particular way. The proteomic study described allowed the correlation between EMT process induced by EGF with translational control, regulation of cell cycle and the change in the energy metabolism.

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Bajaj, Rakhi. "Residue level characterization of molecular interactions of intermembrane space domains governing the preprotein import into the mitochondrial matrix." Doctoral thesis, 2013. http://hdl.handle.net/11858/00-1735-0000-0023-9958-7.

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"Functional analysis of Tim50, a novel subunit of the TIM23 complex that links mitochondrial protein translocation across the outer and inner membranes." Thesis, 2004. http://hdl.handle.net/2237/6355.

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Yamamoto, Hayashi, and 林. 山本. "Functional analysis of Tim50, a novel subunit of the TIM23 complex that links mitochondrial protein translocation across the outer and inner membranes." Thesis, 2004. http://hdl.handle.net/2237/6355.

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Waingankar, Tejashree Pradip. "Understanding the architecture of mitochondrial presequence translocase machinery and its implications in ALS progression." Thesis, 2022. https://etd.iisc.ac.in/handle/2005/5950.

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The current thesis describes the structural organization of the presequence translocase machinery and its functional association with ALS pathogenesis. The TIM23 complex is essential for the mitochondrial biogenesis of polypeptides with N-terminus targeting sequence into the matrix and inner membrane. Hence any defects in the import machinery are known to cause mitochondrial dysfunction affecting cellular homeostasis. The importance of the presequence translocase machinery can be highlighted as its architecture, and overall import mechanisms have remained evolutionary conserved. However, because of the complex nature of a multicellular organism, the human TIM23 complex was proposed to have multiple forms distinguished by their role in housekeeping function and disease association. The findings of the current thesis provide insights into the structural dynamics of the human TIM23 machinery and how variants of an import motor complex protein differentially influence the matrix protein translocation. Additionally, the work focuses on the functional characterization of the presequence translocase machinery under a disease background, wherein the binding of mutant results in the altered translocation of a substrate leading to mitochondrial dysfunction.
CSIR

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Частини книг з теми "TIM23 complex"

Dudek, Jan, Bernard Guiard, and Peter Rehling. "The Role of the TIM23 Complex and Its Associated Motor Complex in Mitochondrial Protein Import." In Molecular Machines Involved in Protein Transport across Cellular Membranes, 387–411. Elsevier, 2007. http://dx.doi.org/10.1016/s1874-6047(07)25015-2.

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Тези доповідей конференцій з теми "TIM23 complex"

Babalic, Corina N. "Integrable discretization of complex mKdV equation and multiple soliton solutions." In PROCEEDINGS OF THE TIM20-21 PHYSICS CONFERENCE. AIP Publishing, 2023. http://dx.doi.org/10.1063/5.0150719.

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Kumar, S. Deepak, V. Sai Mouli, Surya B. Rao, M. Lokesh, T. Venkatesh, M. Upadhyay, and P. S. V. Ramana Rao. "CNC simulation and machining of complex parts - Case study of a bullet profile." In PROCEEDINGS OF THE TIM20-21 PHYSICS CONFERENCE. AIP Publishing, 2023. http://dx.doi.org/10.1063/5.0149972.

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Roberts, Jordan C., Mohammad Motalab, Safina Hussain, Jeffrey C. Suhling, Richard C. Jaeger, and Pradeep Lall. "Characterization of Die Stresses in CBGA Packages due to Component Assembly and Heat Sink Clamping." In ASME 2011 Pacific Rim Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Systems. ASMEDC, 2011. http://dx.doi.org/10.1115/ipack2011-52185.

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Microprocessor packaging in modern workstations and servers often consists of one or more large flip chip die that are mounted to a high performance ceramic chip carrier. The final assembly configuration features a complex stack up of flip chip area array solder interconnects, underfill, ceramic substrate, lid, heat sink, thermal interface materials, second level CBGA solder joints, organic PCB, etc., so that a very complicated set of loads is transmitted to the microprocessor chip. Several trends in the evolution of this packaging architecture have exacerbated die stress levels including the transition to larger die, high CTE ceramic substrates, lead free solder joints, higher levels of power generation, and larger heat sinks with increased clamping forces. Die stress effects are of concern due to several reasons including degradation of silicon device performance (mobility/speed), damage that can occur to the copper/low-k top level interconnect layers, and potential mechanical failure of the silicon in extreme cases. In this work, we have used test chips containing piezoresistive sensors to measure the buildup of mechanical stresses in a microprocessor die after various steps of the CBGA assembly process, as well as due to heat sink clamping. The developed normal stresses are compressive (triaxial compression) across the die surface, with significant in-plane and out-of-plane (interfacial) shear stresses also present at the die corners. The compressive stresses have been found to increase with each assembly step (flip chip solder joint reflow, underfill dispense and cure, lid attachment, CBGA assembly to PCB, and heat sink clamping). Levels exceeding 500 MPa have been observed for extremely high heat sink clamping forces. The utilized (111) silicon test chips were able to measure the complete three-dimensional stress state (all 6 stress components) at each sensor site being monitored by the data acquisition hardware. The test chips had dimensions of 20 × 20 mm, and 3600 lead free solder interconnects (full area array) were used to connect the chips to the high CTE ceramic chip carriers. Before packaging, the sensor resistances were measured by directly probing the individual test chip wafers. The chips were then diced, reflowed to the ceramic substrate, and then underfilled and cured. A metallic lid and second level solder balls were attached to complete the flip chip ceramic BGA components. After every packaging step (flip chip solder ball reflow, underfill dispense and cure, lid attachment and adhesive cure), the sensor resistances were re-measured, so that the die stresses induced by each assembly operation could be characterized. Finally, CBGAs with the stress sensing chips were soldered to organic PCB test boards. A simulated heat sink loading was then applied, and the stresses were measured as a function of the clamping force. The heat sink clamping pressure distribution was monitored using in-situ resistive sensors in the TIM2 position between the lid and heat sink. The measured stress changes due to heat sink clamping where correlated with finite element simulations. With suitable detail in the models, excellent correlation has been obtained.

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