FEBS LettersPub Date : 2021-03-01Epub Date: 2020-10-20DOI: 10.1002/1873-3468.13950
Maki Tsujita, Boris Vaisman, Liu Chengyu, Kasey C Vickers, Kei-Ichiro Okuhira, Sten Braesch-Andersen, Alan T Remaley
{"title":"Apolipoprotein A-I in mouse cerebrospinal fluid derives from the liver and intestine via plasma high-density lipoproteins assembled by ABCA1 and LCAT.","authors":"Maki Tsujita, Boris Vaisman, Liu Chengyu, Kasey C Vickers, Kei-Ichiro Okuhira, Sten Braesch-Andersen, Alan T Remaley","doi":"10.1002/1873-3468.13950","DOIUrl":"https://doi.org/10.1002/1873-3468.13950","url":null,"abstract":"<p><p>Apolipoprotein (apo) A-I, the major structural protein of high-density lipoprotein (HDL), is present in human and mouse cerebrospinal fluid (CSF) despite its lack of expression in brain cells. To identify the origin of apoA-I in CSF, we generated intestine-specific and liver-specific Apoa1 knockout mice (Apoa1<sup>ΔInt</sup> and Apoa1<sup>Δliv</sup> mice, respectively). Lipoprotein profiles of Apoa1<sup>ΔInt</sup> and Apoa1<sup>ΔLiv</sup> mice resembled those of control littermates, whereas knockout of Apoa1 in both intestine and liver (Apoa1<sup>ΔIntΔLiv</sup> ) resulted in a 60-percent decrease in HDL-cholesterol levels, thus strongly mimicking the Apoa1<sup>-/-</sup> mice. Immunoassays revealed that mouse apoA-I was not present in the CSF of the Apoa1<sup>ΔIntΔLiv</sup> mice. Furthermore, apoA-I levels in CSF were highly correlated with plasma spherical HDL levels, which were regulated by ABCA1 and LCAT. Collectively, these results suggest that apoA-I protein in CSF originates in liver and small intestine and is taken up from the plasma.</p>","PeriodicalId":50454,"journal":{"name":"FEBS Letters","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/1873-3468.13950","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38457774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
FEBS LettersPub Date : 2021-03-01Epub Date: 2020-11-28DOI: 10.1002/1873-3468.13991
Eszter Kozák, Bence Szikora, Attila Iliás, Péter K Jani, Zoltán Hegyi, Zsolt Matula, Dóra Dedinszki, Natália Tőkési, Krisztina Fülöp, Viola Pomozi, György Várady, Éva Bakos, Gabor E Tusnády, Imre Kacskovics, Andras Váradi
{"title":"Creation of the first monoclonal antibody recognizing an extracellular epitope of hABCC6.","authors":"Eszter Kozák, Bence Szikora, Attila Iliás, Péter K Jani, Zoltán Hegyi, Zsolt Matula, Dóra Dedinszki, Natália Tőkési, Krisztina Fülöp, Viola Pomozi, György Várady, Éva Bakos, Gabor E Tusnády, Imre Kacskovics, Andras Váradi","doi":"10.1002/1873-3468.13991","DOIUrl":"https://doi.org/10.1002/1873-3468.13991","url":null,"abstract":"<p><p>Mutations in the ABCC6 gene result in calcification diseases such as pseudoxanthoma elasticum or Generalized Arterial Calcification of Infancy. Generation of antibodies recognizing an extracellular (EC) epitope of ABCC6 has been hampered by the short EC segments of the protein. To overcome this limitation, we immunized bovine FcRn transgenic mice exhibiting an augmented humoral immune response with Human Embryonic Kidney 293 cells cells expressing human ABCC6 (hABCC6). We obtained a monoclonal antibody recognizing an EC epitope of hABCC6 that we named mEChC6. Limited proteolysis revealed that the epitope is within a loop in the N-terminal half of ABCC6 and probably spans amino acids 338-347. mEChC6 recognizes hABCC6 in the liver of hABCC6 transgenic mice, verifying both specificity and EC binding to intact hepatocytes.</p>","PeriodicalId":50454,"journal":{"name":"FEBS Letters","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/1873-3468.13991","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38577380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Dynamics and electrostatics define an allosteric druggable site within the receptor-binding domain of SARS-CoV-2 spike protein.","authors":"Sayan Bhattacharjee, Rajanya Bhattacharyya, Jayati Sengupta","doi":"10.1002/1873-3468.14038","DOIUrl":"https://doi.org/10.1002/1873-3468.14038","url":null,"abstract":"<p><p>The pathogenesis of the SARS-CoV-2 virus initiates through recognition of the angiotensin-converting enzyme 2 (ACE2) receptor of the host cells by the receptor-binding domain (RBD) located at the spikes of the virus. Here, using molecular dynamics simulations, we have demonstrated the allosteric crosstalk within the RBD in the apo- and the ACE2 receptor-bound states, revealing the contribution of the dynamics-based correlated motions and the electrostatic energy perturbations to this crosstalk. While allostery, based on correlated motions, dominates inherent distal communication in the apo-RBD, the electrostatic energy perturbations determine favorable pairwise crosstalk within the RBD residues upon binding to ACE2. Interestingly, the allosteric path is composed of residues which are evolutionarily conserved within closely related coronaviruses, pointing toward the biological relevance of the communication and its potential as a target for drug development.</p>","PeriodicalId":50454,"journal":{"name":"FEBS Letters","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/1873-3468.14038","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38824053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Insertion loop-mediated folding propagation governs efficient maturation of hyperthermophilic Tk-subtilisin at high temperatures.","authors":"Ryo Uehara, Nanako Dan, Hiroshi Amesaka, Takuya Yoshizawa, Yuichi Koga, Shigenori Kanaya, Kazufumi Takano, Hiroyoshi Matsumura, Shun-Ichi Tanaka","doi":"10.1002/1873-3468.14028","DOIUrl":"https://doi.org/10.1002/1873-3468.14028","url":null,"abstract":"<p><p>The serine protease Tk-subtilisin from the hyperthermophilic archaeon Thermococcus kodakarensis possesses three insertion loops (IS1-IS3) on its surface, as compared to its mesophilic counterparts. Although IS1 and IS2 are required for maturation of Tk-subtilisin at high temperatures, the role of IS3 remains unknown. Here, CD spectroscopy revealed that IS3 deletion arrested Tk-subtilisin folding at an intermediate state, in which the central nucleus was formed, but the subsequent folding propagation into terminal subdomains did not occur. Alanine substitution of the aspartate residue in IS3 disturbed the intraloop hydrogen-bonding network, as evidenced by crystallographic analysis, resulting in compromised folding at high temperatures. Taking into account the high conservation of IS3 across hyperthermophilic homologues, we propose that the presence of IS3 is important for folding of hyperthermophilic subtilisins in high-temperature environments.</p>","PeriodicalId":50454,"journal":{"name":"FEBS Letters","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/1873-3468.14028","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38368838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Halophilic to mesophilic adaptation of ubiquitin-like proteins.","authors":"Quan Li, Mengqing Li, Cong Li, Xinxin Li, Chenghui Lu, Xiaoming Tu, Zhiyong Zhang, Xuecheng Zhang","doi":"10.1002/1873-3468.14023","DOIUrl":"https://doi.org/10.1002/1873-3468.14023","url":null,"abstract":"Elucidating how proteins adapt from halophilic to mesophilic environments will enable a better understanding of protein evolution and folding. In this study, by directed evolution and site‐directed mutagenesis of the halophilic ubiquitin‐like protein (ULP) Samp2, we find that substitution of the prebiotic amino acid Asp31 by Gly is uniquely effective in the mesophilic adaptation of ULP. Sequence analysis shows that substitution of Asp/Glu in halophilic ULPs by Gly in mesophilic ULPs has higher occurrence than other substitutions, supporting the unique role of the substitution in the mesophilic adaptation of ULP. Molecular dynamic simulations indicate that the mesophilic adaptation might result from the effect of the substitution on the conformational flexibility of ULP.","PeriodicalId":50454,"journal":{"name":"FEBS Letters","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/1873-3468.14023","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38697458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
FEBS LettersPub Date : 2021-02-01Epub Date: 2021-01-24DOI: 10.1002/1873-3468.14029
Jiss Maria Louis, Arjun Agarwal, Raviprasad Aduri, Indrani Talukdar
{"title":"Global analysis of RNA-protein interactions in TNF-α induced alternative splicing in metabolic disorders.","authors":"Jiss Maria Louis, Arjun Agarwal, Raviprasad Aduri, Indrani Talukdar","doi":"10.1002/1873-3468.14029","DOIUrl":"https://doi.org/10.1002/1873-3468.14029","url":null,"abstract":"<p><p>In this report, using the database of RNA-binding protein specificities (RBPDB) and our previously published RNA-seq data, we analyzed the interactions between RNA and RNA-binding proteins to decipher the role of alternative splicing in metabolic disorders induced by TNF-α. We identified 13 395 unique RNA-RBP interactions, including 385 unique RNA motifs and 35 RBPs, some of which (including MBNL-1 and 3, ZFP36, ZRANB2, and SNRPA) are transcriptionally regulated by TNF-α. In addition to some previously reported RBPs, such as RBMX and HuR/ELAVL1, we found a few novel RBPs, such as ZRANB2 and SNRPA, to be involved in the regulation of metabolic syndrome-associated genes that contain an enrichment of tetrameric RNA sequences (AUUU). Taken together, this study paves the way for novel RNA-protein interaction-based therapeutics for treating metabolic syndromes.</p>","PeriodicalId":50454,"journal":{"name":"FEBS Letters","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/1873-3468.14029","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38796930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Ubiquitin-independent proteasomal degradation of Spindlin-1 by the E3 ligase HACE1 contributes to cell-cell adhesion.","authors":"Vivek Reddy Palicharla, Devanshi Gupta, Debjani Bhattacharya, Subbareddy Maddika","doi":"10.1002/1873-3468.14031","DOIUrl":"https://doi.org/10.1002/1873-3468.14031","url":null,"abstract":"<p><p>HECT-E3 ligases play an essential role in catalyzing the transfer of ubiquitin to protein substrates. The noncatalytic roles of HECT-E3 ligases in cells are unknown. Here, we report that a HECT-E3 ligase, HACE1, functions as an adaptor independent of its E3 ligase activity. We identified Spindlin-1, a histone reader, as a new HACE1-associated protein. Interestingly, we found that HACE1 promotes Spindlin-1 degradation via the proteasome in an ubiquitination-independent manner. Functionally, we demonstrated that the loss of HACE1 results in weak cell-cell adhesion due to Spindlin-1-mediated accumulation of GDNF, a negative regulator of cell adhesion. Together, our data suggest that HACE1 acts as a molecular adaptor and plays an important noncatalytic role in presenting selected substrates directly to the proteasome for degradation.</p>","PeriodicalId":50454,"journal":{"name":"FEBS Letters","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/1873-3468.14031","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38799457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
FEBS LettersPub Date : 2021-02-01Epub Date: 2021-01-06DOI: 10.1002/1873-3468.14030
Siyue Qin, Ling Ye, Youshi Zheng, Ju Gao
{"title":"Cytosolic PINK1 orchestrates protein translation during proteasomal stress by phosphorylating the translation elongation factor eEF1A1.","authors":"Siyue Qin, Ling Ye, Youshi Zheng, Ju Gao","doi":"10.1002/1873-3468.14030","DOIUrl":"https://doi.org/10.1002/1873-3468.14030","url":null,"abstract":"<p><p>Mutations in PINK1 (PTEN-induced putative kinase 1) are associated with autosomal recessive early-onset Parkinson's disease. Full-length PINK1 (PINK1-l) has been extensively studied in mitophagy; however, the functions of the short form of PINK1 (PINK1-s) remain poorly understood. Here, we report that PINK1-s is recruited to ribosome fractions after short-term inhibition of proteasomes. The expression of PINK1-s greatly inhibits protein synthesis even without proteasomal stress. Mechanistically, PINK1-s phosphorylates the translation elongation factor eEF1A1 during proteasome inhibition. The expression of the phosphorylation mimic mutation eEF1A1S396E rescues protein synthesis defects and cell viability caused by PINK1 knockout. These findings implicate an important role for PINK1-s in protecting cells against proteasome stress through inhibiting protein synthesis.</p>","PeriodicalId":50454,"journal":{"name":"FEBS Letters","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/1873-3468.14030","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39080104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
FEBS LettersPub Date : 2021-02-01Epub Date: 2021-01-02DOI: 10.1002/1873-3468.14027
Ruchir Rastogi, Jitender Kumar Verma, Vijay Singh, Ganga Krishnamurthy, Chandni Sood, Anjali Kapoor, Kamal Kumar, Irshad Ansari, Amitabha Mukhopadhyay
{"title":"Identification and characterization of the hemoglobin-binding domain of hemoglobin receptor in Leishmania.","authors":"Ruchir Rastogi, Jitender Kumar Verma, Vijay Singh, Ganga Krishnamurthy, Chandni Sood, Anjali Kapoor, Kamal Kumar, Irshad Ansari, Amitabha Mukhopadhyay","doi":"10.1002/1873-3468.14027","DOIUrl":"https://doi.org/10.1002/1873-3468.14027","url":null,"abstract":"<p><p>Leishmania internalize hemoglobin (Hb) via a specific receptor (HbR) for their survival. To identify the Hb-binding domain of HbR, we cloned and expressed several truncated proteins of HbR and determined their ability to bind Hb. Our findings reveal that 90% of Hb-binding activity is retained in HbR<sup>41-80</sup> in comparison with HbR<sup>1-471</sup> . We synthesized a 40 amino acid peptide (SSEKMKQLTMYMIHEMVEGLEGRPSTVRMLPSFVYTSDPA) corresponding to HbR<sup>41-80</sup> and found that it specifically binds Hb. Subsequently, we found that the HbR<sup>41-80</sup> peptide completely blocks Hb uptake in both promastigote and amastigote forms of Leishmania and, thereby, inhibits the growth of the parasite. These results demonstrate that HbR<sup>41-80</sup> is the Hb-binding domain of HbR, which might be used as a potential therapeutic agent to inhibit the growth of Leishmania.</p>","PeriodicalId":50454,"journal":{"name":"FEBS Letters","volume":null,"pages":null},"PeriodicalIF":3.5,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1002/1873-3468.14027","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38368840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}