Sadik Bay

Dr. Sadik Bay

orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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23 June 2023 in Nature Communications
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ARAnna Rodina
Anna Rodina
CXChao Xu
Chao Xu
CDChander Singh Digwal
Chander Singh Digwal
SJSuhasini Joshi
Suhasini Joshi
YPYogita Patel
Yogita Patel
GCGabriela Chiosis
Gabriela Chiosis
Systems-level assessments of protein-protein interaction (PPI) network dysfunctions are currently out-of-reach because approaches enabling proteome-wide identification, analysis, and modulation of context-specific PPI changes in native (unengineered) cells and tissues are lacking. Herein, we take advantage of chemical binders of maladaptive scaffolding structures termed epichaperomes and develop an epichaperome-based ‘omics platform, epichaperomics, to identify PPI alterations in disease. We provide multiple lines of evidence, at both biochemical and functional levels, demonstrating the importance of these probes to identify and study PPI network dysfunctions and provide mechanistically and therapeutically relevant proteome-wide insights. As proof-of-principle, we derive systems-level insight into PPI dysfunctions of cancer cells which enabled the discovery of a context-dependent mechanism by which cancer cells enhance the fitness of mitotic protein networks. Importantly, our systems levels analyses support the use of epichaperome chemical binders as therapeutic strategies aimed at normalizing PPI networks.

16 October 2024 in Nature Communications
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TRTanaya Roychowdhury
Tanaya Roychowdhury
SMSeth W. McNutt
Seth W. McNutt
CPChiranjeevi Pasala
Chiranjeevi Pasala
HNHieu T. Nguyen
Hieu T. Nguyen
DTDaniel T. Thornton
Daniel T. Thornton
FCFeixia Chu
Feixia Chu
The intricate network of protein-chaperone interactions is crucial for maintaining cellular function. Recent discoveries have unveiled the existence of specialized chaperone assemblies, known as epichaperomes, which serve as scaffolding platforms that orchestrate the reconfiguration of protein-protein interaction networks, thereby enhancing cellular adaptability and proliferation. This study explores the structural and regulatory aspects of epichaperomes, with a particular focus on the role of post-translational modifications (PTMs) in their formation and function. A key finding is the identification of specific PTMs on HSP90, particularly at residues Ser226 and Ser255 within an intrinsically disordered region, as critical determinants of epichaperome assembly. Our data demonstrate that phosphorylation of these serine residues enhances HSP90’s interactions with other chaperones and co-chaperones, creating a microenvironment conducive to epichaperome formation. Moreover, we establish a direct link between epichaperome function and cellular physiology, particularly in contexts where robust proliferation and adaptive behavior are essential, such as in cancer and pluripotent stem cell maintenance. These findings not only provide mechanistic insights but also hold promise for the development of novel therapeutic strategies targeting chaperone assemblies in diseases characterized by epichaperome dysregulation, thereby bridging the gap between fundamental research and precision medicine.

28 December 2017 in Journal of Biochemical and Molecular Toxicology
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OEOGUZ ERYILMAZ
OGUZ ERYILMAZ
PAPerihan Seda Ateş
Perihan Seda Ateş
IÜİsMail Ünal
İsMail Ünal
ÜÜÜnsal Veli Üstündağ
Ünsal Veli Üstündağ
SBSadik Bay
Sadik Bay
MAMehmet Akalın
Mehmet Akalın

1 November 2020 in International Journal of Nanomedicine
Verified
Journal Article
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EYElif Nur Yilmaz
Elif Nur Yilmaz
SBSadik Bay
Sadik Bay
GOGurkan Ozturk
Gurkan Ozturk
MUMehmet Hikmet Ucisik
Mehmet Hikmet Ucisik
Purpose: Curcumin, a polyphenol isolated from the rhizomes of turmeric, holds great potential as a neuroprotective agent in addition to its anti-inflammatory and antioxidant characteristics. The poor bioavailability and low stability of curcumin are the greatest barriers to its clinical use. This study aims to investigate the neuroprotective effect of curcumin on axonal injury, by delivering the lipophilic polyphenol to a primary hippocampal neuron culture by means of a lipid-based drug delivery system, named emulsomes. Methods: To study neuroregeneration ex vivo, an injury model was established through single-cell laser axotomy on hippocampal neurites. Upon treatment with curcumin-loaded emulsomes (CurcuEmulsomes), curcumin and CurcuEmulsome uptake into neurons was verified by three-dimensional Z-stack images acquired with confocal microscopy. Neuron survival after axonal injury was tracked by propidium iodide (PI) and Hoechst staining. Alterations in expression levels of physiological markers, such as anti-apoptotic marker Bcl2, apoptotic marker cleaved caspase 3, neuroprotective marker Wnt3a and the neuronal survival marker mTOR, were investigated by immunocytochemistry analyses. Results: The results indicated significant improvement in the survival rate of injured neurons upon CurcuEmulsome treatment. Bcl2 expression was significantly higher for injured neurons treated with curcumin or CurcuEmulsome. Reduction in caspase 3 expression was seen in both curcumin and CurcuEmulsome treatment, whereas there were no significant changes in Wnt3a and mTOR expression. Conclusion: The established laser-axotomy model was proven as a reliable methodology to study neurodegenerative models ex vivo. CurcuEmulsomes delivered curcumin to primary hippocampal neurons successfully. Treated with CurcuEmulsomes, injured hippocampal neurons benefit from the neuroprotective effects of curcumin, exhibiting a higher survival rate and increased anti-apoptotic marker levels.

3 October 2020 in Journal of Tissue Engineering and Regenerative Medicine
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USUmran Aydemir Sezer
Umran Aydemir Sezer
KYKevser Ozturk Yavuz
Kevser Ozturk Yavuz
GOGizem Ors
Gizem Ors
SBSadik Bay
Sadik Bay
BABasak Aru
Basak Aru
HKHuseyin Karaca
Huseyin Karaca

14 May 2020 in PLOS ONE
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Journal Article
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NKNihal Karakaş
Nihal Karakaş
SBSadik Bay
Sadik Bay
NTNezaket Türkel
Nezaket Türkel
NÖNurşah Öztunç
Nurşah Öztunç
MÖMerve Öncül
Merve Öncül
GÖGürkan Öztürk
Gürkan Öztürk
Mesenchymal stem cells have the ability to transdifferentiate into neurons and therefore one of the potential adult stem cell source for neuronal tissue regeneration applications and understanding neurodevelopmental processes. In many studies on human mesenchymal stem cell (hMSC) derived neurons, success in neuronal differentiation was limited to neuronal protein expressions which is not statisfactory in terms of neuronal activity. Established neuronal networks seen in culture have to be investigated in terms of synaptic signal transmission ability to develop a culture model for human neurons and further studying the mechanism of neuronal differentiation and neurological pathologies. Accordingly, in this study, we analysed the functionality of bone marrow hMSCs differentiated into neurons by a single step cytokine-based induction protocol. Neurons from both primary hMSCs and hMSC cell line displayed spontaneous activity (≥75%) as demonstrated by Ca++ imaging. Furthermore, when electrically stimulated, hMSC derived neurons (hMd-Neurons) matched the response of a typical neuron in the process of maturation. Our results reveal that a combination of neuronal inducers enhance differentiation capacity of bone marrow hMSCs into high yielding functional neurons with spontaneous activity and mature into electrophysiologically active state. Conceptually, we suggest these functional hMd-Neurons to be used as a tool for disease modelling of neuropathologies and neuronal differentiation studies.