Honghong Chen, Yi X Li, Robert S Wong, Jessica L Esseltine, Donglin Bai
Mutations in more than half of human connexin genes encoding gap junction subunits have been linked to inherited human diseases. Functional studies of human gap junction (GJ) channels are essential for revealing mechanistic insights on the etiology of disease-linked connexin mutants. However, the commonly used Xenopus oocytes, N2A, HeLa, and other model cells for recombinant expression of human connexins have different and significant limitations. Here we developed a human cell line (HEK293) with each of the endogenous connexins (Cx43 and Cx45) knocked out using the CRISPR-Cas9 system...
May 16, 2024: Biochemical Journal
Martín Fló Díaz, Leonardo Pellizza, Rosario Duran, Beatriz Alvarez, Cecilia Fernández
Typical Kunitz proteins (I2 family of the MEROPS database, Kunitz-A family) are metazoan competitive inhibitors of serine peptidases that form tight complexes of 1:1 stoichiometry, mimicking substrates. The cestode Echinococcus granulosus, the dog tapeworm causing cystic echinococcosis in humans and livestock, encodes an expanded family of monodomain Kunitz proteins, some of which are secreted to the dog host interface. The Kunitz protein EgKU-7 contains, in addition to the Kunitz domain with the anti-peptidase loop comprising a critical arginine, a C-terminal extension of about 20 amino acids...
May 16, 2024: Biochemical Journal
Stefanie Jill Hodapp, Nathan Gravel, Natarajan Kannan, Alexandra C Newton
The Ca2+-independent, but diacylglycerol-regulated, novel protein kinase C (PKC) theta (θ) is highly expressed in hematopoietic cells where it participates in immune signaling and platelet function. Mounting evidence suggests that PKCθ may be involved in cancer, particularly blood cancers, breast cancer, and gastrointestinal stromal tumors (GISTs), yet how to target this kinase (as an oncogene or as a tumor suppressor) has not been established. Here, we examine the effect of four cancer-associated mutations, R145H/C in the autoinhibitory pseudosubstrate, E161K in the regulatory C1A domain, and R635W in the regulatory C-terminal tail, on the cellular activity and stability of PKCθ...
May 16, 2024: Biochemical Journal
Emma L Brudenell, Manoj B Pohare, Domen Zafred, Janine Phipps, Hailey R Hornsby, John Darby, Junxiao Dai, Ellen Liggett, Kathleen Cain, Perdita Barran, Thushan I de Silva, Jon R Sayers
The fundamental biology of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) nucleocapsid protein (Ncap), its use in diagnostic assays and its potential application as a vaccine component have received considerable attention since the outbreak of the Covid19 pandemic in late 2019.  Here we report the scalable expression and purification of soluble, immunologically active, SARS-CoV-2 Ncap in Escherichia coli. Codon-optimised synthetic genes encoding the original Ncap sequence and four common variants with an N-terminal 6His affinity tag (sequence MHHHHHHG) were cloned into an inducible expression vector carrying a regulated bacteriophage T5 synthetic promoter controlled by lac operator binding sites...
May 7, 2024: Biochemical Journal
Paramesha Bugga, Michael W Stoner, Janet R Manning, Bellina Mushala, Nisha Bhattarai, Maryam Sharifi-Sanjani, Bradley R Webster, Dharendra Thapa, Iain Scott
GCN5L1, also known as BLOC1S1 and BLOS1, is a small intracellular protein involved in a number of key biological processes. Over the last decade, GCN5L1 has been implicated in the regulation of protein lysine acetylation, energy metabolism, endo-lysosomal function, and cellular immune pathways. An increasing number of published papers have used commercially-available reagents to interrogate GCN5L1 function. However, in many cases these reagents have not been rigorously validated, leading to potentially misleading results...
April 29, 2024: Biochemical Journal
Anil Kumar Singh, Vishal Upadhyay, Arppita Sethi, Sangita Chaowdhury, Shivkant Mishra, Shailednra Prasad Verma, Madan Lal Brahma Bhatt, Arun Kumar Trivedi
E3 ubiquitin ligase, ring finger protein 138 (RNF138) is involved in several biological processes; however, its role in myeloid differentiation or tumorigenesis remains unclear. RNAseq data from TNMplot showed that RNF138 mRNA levels are highly elevated in Acute Myeloid Leukemia (AML) bone marrow samples as compared to bone marrow of normal volunteers. Here, we show that RNF138 serves as an E3 ligase for the tumor suppressor CCAAT/enhancer binding protein (C/EBPα) and promotes its degradation leading to myeloid differentiation arrest in AML...
April 26, 2024: Biochemical Journal
Oliver Baum
Knowledge of the primary structure of neuronal NO synthase (nNOS) in skeletal muscle is still conflicting and needs further clarification. To elucidate the expression patterns of nNOS isoforms at both mRNA and protein level, systematic RT-PCR and epitope mapping by qualitative immunoblot analysis on skeletal muscle of C57/BL6 mice were performed. The ability of the nNOS isoforms to form aggregates was characterized by native low-temperature polyacrylamide electrophoresis (LT-PAGE). The molecular analysis was focused on the rectus femoris (RF) muscle, a skeletal muscle with a nearly balanced ratio of nNOS alpha- and beta-isoforms...
April 9, 2024: Biochemical Journal
Simon A Hawley, Fiona M Russell, D Grahame Hardie
The AMP-activated protein kinase (AMPK) is a sensor of cellular energy status. When activated by increases in ADP:ATP and/or AMP:ATP ratios (signalling energy deficit), AMPK acts to restore energy balance. Binding of AMP to one or more of three CBS repeats (CBS1, CBS3, CBS4) on the AMPK-γ subunit activates the kinase complex by three complementary mechanisms: (i) promoting α-subunit Thr172 phosphorylation by the upstream kinase LKB1; (ii) protecting against Thr172 dephosphorylation; (iii) allosteric activation...
April 9, 2024: Biochemical Journal
Duaa Al-Sadeq, Carolina Conter, Angelos Thanassoulas, Nader Al-Dewik, Bared Safieh-Garabedian, Luis Alfonso Luis Alfonso Martínez-Cruz, Gheyath Nasrallah, Alessandra Astegno, Michail Nomikos
Homocystinuria is a rare disease caused by mutations in the CBS gene that results in a deficiency of cystathionine β-synthase (CBS). CBS is an essential pyridoxal 5'-phosphate (PLP)-dependent enzyme in the transsulfuration pathway, responsible for combining serine with homocysteine to produce cystathionine, whose activity is enhanced by the allosteric regulator S-adenosylmethionine (SAM). CBS also plays a role in generating hydrogen sulfide (H2S), a gaseous signaling molecule with diverse regulatory functions within the vascular, nervous, and immune systems...
April 2, 2024: Biochemical Journal
Kylie A Vestal, Chandramohan Kattamuri, Muhasin Koyiloth, Luisina Ongaro, James A Howard, Aimee Deaton, Simina Ticau, Aditi Dubey, Daniel J Bernard, Thomas B Thompson
Activins are one of the three distinct subclasses within the greater Transforming Growth Factor β (TGFβ) superfamily. First discovered for their critical roles in reproductive biology, activins have since been shown to alter cellular differentiation and proliferation. At present, members of the activin subclass include activin A (ActA), ActB, ActC, ActE, and the more distant members myostatin and GDF11. While the biological roles and signaling mechanisms of most activins class members have been well-studied, the signaling potential of ActE has remained largely unknown...
March 27, 2024: Biochemical Journal
Renuka Shanmugam, Reuben Anderson, Anja H Schiemann, Evelyn Sattlegger
The protein kinase Gcn2 and its effector protein Gcn1 are part of the General Amino Acid Control signalling (GAAC) pathway best known in yeast for its function in maintaining amino acid homeostasis.  Under amino acid limitation, Gcn2 becomes activated, subsequently increasing the levels of phosphorylated eIF2α (eIF2α-P).  This leads to the increased translation of transcriptional regulators, such as Gcn4 in yeast and ATF4 in mammals, and subsequent re-programming of the cell's gene transcription profile, thereby allowing cells to cope with starvation...
March 5, 2024: Biochemical Journal
Jackson E Stewart, Jenna M Crawford, William E Mullen, Angelica Jacques, Michael W Stoner, Iain Scott, Dharendra Thapa
Cardiac mitochondrial dysfunction is a critical contributor to the pathogenesis of aging and many age-related conditions. As such, complete control of mitochondrial function is critical to maintain cardiac efficiency in the aged heart. Lysine acetylation is a reversible post-translational modification shown to regulate several mitochondrial metabolic and biochemical processes. In the present study, we investigated how mitochondrial lysine acetylation regulates fatty acid oxidation and cardiac function in the aged heart...
February 23, 2024: Biochemical Journal
Laura Weatherdon, Kate Stuart, Megan A Cassidy, Alberto Moreno de la Gándara, Hanneke Okkenhaug, Markus Muellener, Grahame Mckenzie, Simon J Cook, Rebecca Gilley
The RAS-regulated RAF-MEK1/2-ERK1/2 signalling pathway is activated in cancer due to mutations in RAS proteins (especially KRAS), BRAF, CRAF, MEK1 and MEK2. Whilst inhibitors of KRASG12C (lung adenocarcinoma) and BRAF and MEK1/2 (melanoma and colorectal cancer) are clinically approved, acquired resistance remains a problem. Consequently, the search for new inhibitors (especially of RAS proteins), new inhibitor modalities and regulators of this pathway, which may be new drug targets, continues and increasingly involves cell-based screens with small molecules or genetic screens such as RNAi, CRISPR or Protein Interference...
February 21, 2024: Biochemical Journal
Arline Fernández-Silva Ana L Juárez-Vázquez Lilian González-Segura Javier Andrés Juárez-Díaz Rosario A Muñoz-Clares
No abstract text is available yet for this article.
May 22, 2024: Biochemical Journal
Eduardo T Cánepa, Bruno G Berardino
Early-life adversities, whether prenatal or postnatal exposure, have been linked to adverse mental health outcomes later in life increasing the risk of several psychiatric disorders. Research on its neurobiological consequences demonstrated an association between exposure to adversities and persistent alterations in the structure, function, and connectivity of the brain. Consistent evidence supports the idea that regulation of gene expression through epigenetic mechanisms are involved in embedding the impact of early-life experiences in the genome and mediate between social environments and later behavioral phenotypes...
May 22, 2024: Biochemical Journal
Chunyang Du, Tao Zhang, Xia Xiao, Yonghong Shi, Huijun Duan, Yunzhuo Ren
No abstract text is available yet for this article.
April 10, 2024: Biochemical Journal
Barry Wilbourn, Darren N Nesbeth, Linda J Wainwright, Mark C Field
No abstract text is available yet for this article.
April 10, 2024: Biochemical Journal
Benjamin M Foster, Zijuan Wang, Christine K Schmidt
Maintaining stability of the genome requires dedicated DNA repair and signalling processes that are essential for the faithful duplication and propagation of chromosomes. These DNA damage response (DDR) mechanisms counteract the potentially mutagenic impact of daily genotoxic stresses from both exogenous and endogenous sources. Inherent to these DNA repair pathways is the activity of protein factors that instigate repair processes in response to DNA lesions. The regulation, coordination, and orchestration of these DDR factors is carried out, in a large part, by post-translational modifications, such as phosphorylation, ubiquitylation, and modification with ubiquitin-like proteins (UBLs)...
April 10, 2024: Biochemical Journal
Amina Djurabekova, Jonathan Lasham, Oleksii Zdorevskyi, Volker Zickermann, Vivek Sharma
Respiratory complex I is a redox-driven proton pump. Several high-resolution structures of complex I have been determined providing important information about the putative proton transfer paths and conformational transitions that may occur during catalysis. However, how redox energy is coupled to the pumping of protons remains unclear. In this article, we review biochemical, structural and molecular simulation data on complex I and discuss several coupling models, including the key unresolved mechanistic questions...
April 10, 2024: Biochemical Journal
Anastasiya Potapenko, Jennilee M Davidson, Albert Lee, Angela S Laird
Machado-Joseph disease (MJD) is a devastating and incurable neurodegenerative disease characterised by progressive ataxia, difficulty speaking and swallowing. Consequently, affected individuals ultimately become wheelchair dependent, require constant care, and face a shortened life expectancy. The monogenic cause of MJD is expansion of a trinucleotide (CAG) repeat region within the ATXN3 gene, which results in polyglutamine (polyQ) expansion within the resultant ataxin-3 protein. While it is well established that the ataxin-3 protein functions as a deubiquitinating (DUB) enzyme and is therefore critically involved in proteostasis, several unanswered questions remain regarding the impact of polyQ expansion in ataxin-3 on its DUB function...
March 20, 2024: Biochemical Journal
Fetch more papers »
Fetching more papers... Fetching...
Remove bar
Read by QxMD icon Read

Save your favorite articles in one place with a free QxMD account.


Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"

We want to hear from doctors like you!

Take a second to answer a survey question.