RESUMO
Gallbladder cancer (GBC) is an uncommon malignancy that is highly aggressive in the advanced stages. However, it rarely metastasizes to the mandible. Numb chin syndrome (NCS) is a rare neurological manifestation associated with various underlying causes, including occult primary cancers and distant metastases. It is often considered to be a significant indicator of malignancy, and thorough investigation is essential in the presence of unclear etiology. The current study reported on the case of a 69-year-old Japanese woman who presented with numbness and mild pain in the lower lip and chin area for three months. No other systemic symptoms were observed. Immunocytochemical examination revealed the presence of an adenocarcinoma and TNM staging as per the Union for International Cancer Control and the American Joint Committee on Cancer guidelines confirmed stage IVb GBC. Comprehensive full-body positron emission tomography-computed tomography examination using 18F-fluoro-2-deoxy-D-glucose revealed additional bone and soft-tissue metastases. Palliative chemotherapy and radiation treatment were initiated based on the advanced stage of disease at the time of diagnosis. However, the patient succumbed to multiple organ failure six months later. The simultaneous occurrence of GBC, mandibular metastasis and NCS is rare and associated with poor prognosis. Despite the widespread nature of the disease, it can often manifest as non-specific oral symptoms without any systemic indications. The current study emphasizes the critical importance of timely confirmatory testing for accurate diagnosis and initiation of appropriate management for such complex conditions.
RESUMO
Odontogenic keratocysts (OKCs) often occur in the molars in the mandibular ramus; they often progress asymptomatically and are discovered only after widespread development. Some cases of OKC progress to the mandibular condyle; however, very few cases exist only in the condyle. To the best of our knowledge, in all of the previously reported cases, OKCs occurred in the mandibular ramus, which underwent resection. The present study reports the case of a 31-year-old man in whom an OKC (13x12x6 mm) occurred discretely in the base of the condyle, in which the condylar head was successfully preserved. The tumor was removed under general anesthesia using the approach of shaving the anterior surface of the mandible. The extraction cavity was managed using the packed open technique and with an obturator. Approximately 20 months post-operation, the patient remained recurrence-free. This report presents a rare case of an OKC in the mandibular condyle base region. Resection was performed under general anesthesia and the condylar process was successfully preserved.
RESUMO
BACKGROUND: The coexistence of calcium pyrophosphate dihydrate crystal deposition (CPP) and synovial chondromatosis (SC) in the temporomandibular joint (TMJ) is rarely reported. CPP disease (CPPD) is complex arthritis synonymous with excessive pyrophosphate production and variable aberrations in mineral and organic phase metabolism of the joint cartilage, leading to local inundated CPP and crystal deposition of partially deciphered predispositions. Meanwhile, SC is a rare benign synovial joint proliferative disease of unclear etiology and has a low risk of malignant transformation. However, SC manifests severe joint disability and dysfunction because of connective tissue metaplasia of the synovial membrane, which forms cartilaginous nodules with or without calcifications or ossifications. These nodules often detach and form intra-articular loose bodies and very rarely within extraarticular spaces. CASE PRESENTATION: We report the case of a 61-year-old man to expand the body of literature on these unusual coexisting arthropathies of the TMJ. The patient presented to our hospital in 2020 with complaints of pain in the right TMJ and trismus for over 6 months. Radiographic assessments of the TMJ provided a preoperative provisional diagnosis of SC. However, the histopathology of the open biopsy revealed tumor-like lesions comprising several deposits of rhomboid and rod-shaped crystals that displayed positive birefringence in polarized light, confirming a coexistence of CPPD. A second-stage operation was performed for the complete removal of the loose bodies and chalk-like lesions including synovectomy. No evidence of recurrence was recorded after a follow-up of nearly 1.5 years. CONCLUSIONS: Isolated CPPD and SC of the TMJ are prevalent in the literature however, monoarticular coexistence of these diseases is rare, due to the lack of consistency in the diagnostic criteria in clinical practice. Moreover, optimal treatment depends on several considerations. This report delineated the molecular etiopathology and underscored the need for continued deciphering of the causal mechanisms of coexisting CPPD and SC of the TMJ. In addition, the importance of confirmatory testing for accurate diagnosis, and appropriate management of these diseases were discussed.
Assuntos
Condrocalcinose , Condromatose Sinovial , Transtornos da Articulação Temporomandibular , Masculino , Humanos , Pessoa de Meia-Idade , Condromatose Sinovial/complicações , Condromatose Sinovial/diagnóstico por imagem , Condromatose Sinovial/cirurgia , Pirofosfato de Cálcio , Transtornos da Articulação Temporomandibular/complicações , Articulação Temporomandibular , Condrocalcinose/diagnóstico , Condrocalcinose/diagnóstico por imagemRESUMO
BACKGROUND/AIM: Oral squamous cell carcinoma (OSCC) is a common malignancy with poor prognosis. Therefore, novel therapeutic options are needed to improve prognosis of OSCC. Recently, microRNAs (miRs) have received increasing attention as a potential therapeutic tool for carcinomas. However, no definitive miR-based drugs for patients with OSCC have been reported to date. The aim of this study was to identify new miRs potentially involved in cellular processes associated with OSCC malignancy, which could lead to novel therapeutic strategies. MATERIALS AND METHODS: We identified miRs that are modulated in OSCC and possibly regulate OSCC malignancy, using miR microarray on OSCC cell lines. RESULTS: miR-935 and miR-509-3p were down-regulated in OSCC cell lines and patient tissues. When miR-935 was overexpressed in HSC-3-M3 cells, proliferation, migration, and invasion of the cell line was suppressed, whereas apoptosis was increased. Moreover, we showed that the gene inositol polyphosphate-4-phosphatase type I A (INPP4A) is a potential target whose expression is positively regulated by miR-935. CONCLUSION: miR-935 may function as a tumor suppressor by inhibiting OSCC malignancy via INPP4A induction. Therefore, miR-935 can be a new therapeutic candidate for OSCC treatment.
Assuntos
Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/genética , MicroRNAs/metabolismo , Neoplasias Bucais/enzimologia , Neoplasias Bucais/genética , Monoéster Fosfórico Hidrolases/metabolismo , Apoptose/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Neoplasias Bucais/patologia , Invasividade Neoplásica , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genéticaRESUMO
Currently, Kaposi's sarcoma (KS) is treated following the recommendations of international guidelines. These guidelines recommend esophagogastroduodenoscopy/colonoscopy for detecting multicentric KS of visceral lesions. Second primary malignancies (SPMs) are also a common KS complication; however, information on their detection and treatment is unfortunately not yet indicated in these guidelines. This paper reports on an 86-year-old man who suffered from quadruple primary malignancies: skin classic KS with colon adenocarcinoma, oral squamous cell carcinoma (maxilla), and well-differentiated stomach adenocarcinoma. Gastric cancer was incidentally detected during esophagogastroduodenoscopy, which was performed to detect visceral KS. We suggest that esophagogastroduodenoscopy/colonoscopy be routinely performed during the follow-up of patients with KS. As SPMs are crucial complications in patients with KS, these malignancies should be detected as early as possible.
RESUMO
The occurrence of second primary tumor (SPT)following malignancy treatment is common. In patients with head and neck (H&N) cancer, SPTs principally occur in the H&N region, lungs or esophagus. Therefore, patient follow-up after cancer treatment is important in order to detect recurrence, metastasis and new primary tumors. However, no standard guidelines on lifelong follow-up imaging are available. Herein, we report a patient who presented with three metachronous primary tumors-squamous cell carcinoma (SCC) of the tongue, SCC of the lip and type A thymoma. The third tumor was incidentally detected during follow-up using contrast-enhanced computed tomography (CT) 9 years following resection of the second tumor. To the best of our knowledge, this specific combination of metachronous tumors has not yet been reported. Based on the literature review, we observed that thymoma occurs following H&N cancer treatment. Therefore, to ensure that the presence of subsequent thymomas is not overlooked, we suggest regular lifelong follow-up using contrast-enhanced CT in patients who had previously been diagnosed with H&N cancer. The literature review revealed that thymomas occur in patients with H&N cancer and should be detected at the earliest convenience.
RESUMO
Amyloid-ß (Aß) plays a central role in the pathogenesis of Alzheimer's disease (AD). Because AD pathologies begin two decades before the onset of dementia, prevention of Aß amyloidosis has been proposed as a mean to block the pathological cascade. Here, we generate a transgenic plant-based vaccine, a soybean storage protein containing Aß4-10, named Aß+, for oral Aß immunization. One mg of Aß+ or control protein (Aß-) was administered to TgCRND8 mice once a week from 9 weeks up to 58 weeks. Aß+ immunization raised both anti-Aß antibodies and cellular immune responses. Spatial learning decline was prevented in the Aß+ immunized group in an extended reference memory version of Morris water maze test from 21 to 57 weeks. In Tris-buffered saline (TBS), sodium dodecyl sulfate (SDS), and formic acid (FA) serial extractions, all sets of Aß species from Aß monomer, low to high molecular weight Aß oligomers, and Aß smears had different solubility in TgCRND8 brains. Aß oligomers decreased in TBS fractions, corresponding to an increase in high molecular weight Aß oligomers in SDS extracts and Aß smears in FA fraction of the Aß+ treated group. There was significant inhibition of histological Aß burden, especially in diffuse plaques, and suppression of microglial inflammation. Processing of amyloid-ß protein precursor was not different between Aß+ and Aß- groups. No evidence of amyloid-related inflammatory angiopathy was observed. Thus, Aß+ oral immunization could be a promising, cheap, and long-term safe disease-modifying therapy to prevent the pathological process in AD.
Assuntos
Peptídeos beta-Amiloides/administração & dosagem , Disfunção Cognitiva/prevenção & controle , Imunização/métodos , Plantas Geneticamente Modificadas , Proteínas de Soja/administração & dosagem , Aprendizagem Espacial/efeitos dos fármacos , Administração Oral , Animais , Disfunção Cognitiva/genética , Disfunção Cognitiva/metabolismo , Humanos , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C3H , Camundongos Transgênicos , Plantas Geneticamente Modificadas/genética , Estrutura Secundária de Proteína , Proteínas de Armazenamento de Sementes/administração & dosagem , Proteínas de Armazenamento de Sementes/genética , Proteínas de Soja/química , Proteínas de Soja/genética , Aprendizagem Espacial/fisiologiaRESUMO
Second primary cancer (SPC) is an important prognostic factor for patients with head and neck cancer (HNC); therefore, the association between the prognosis and development of SPC has been well-reported. The use of 2-[18F]-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) is valuable to examine cancer stage, evaluate treatment responses and investigate suspected relapses or metastases. In the present study, the case of a male patient who was diagnosed with three primary cancer types, including well to moderately differentiated squamous cell carcinoma (SCC) of the mandible, axillary cutaneous poorly differentiated SCC and prostate adenocarcinoma, was described. Among these, mandible cancer was the first diagnosed when the patient was 70 years of age. Synchronous skin and prostate cancer (PRC) types then developed 3 years later. To the best of our knowledge, this is the first report of the aforementioned combination of cancer types. Postoperative FDG-PET was not performed as no lesions of recurrence or metastases of mandible cancer were found. Three years later, the PRC was asymptomatic and was incidentally detected by FDG-PET performed for a preoperative evaluation of skin cancer. It was indicated that FDG-PET could be utilized in patients with HNC due to there being no accurate FDG-PET protocol to detect SPC over a long-term follow-up.
RESUMO
Second primary malignancy (SPM) is a severe issue for cancer survivors, particularly for osteosarcoma (OS) survivors. To date, the associations between subsequent SPM and OS have been well reported. Hematogenic and solid malignancies tend to occur following OS treatment. Reportedly, 2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) is mainly used in OS patients for initial cancer staging, to evaluate the response of neoadjuvant chemotherapy, and when recurrence or metastasis is clinically suspected. The present case report describes a 70-year-old man diagnosed with three primary malignancies: jaw OS, myelodysplastic syndrome and colorectal adenocarcinoma. To the best of our knowledge, this combination of malignancies has not been reported previously. Until now, there is no specific protocol of postoperative FDG-PET for OS patients. Few studies have described OS follow-up methods; therefore, there is no consensus on proper follow-up methods. In the present case report, the colorectal early-stage SPM was observed, without any symptoms, by FDG-PET/computed tomography. To avoid overlooking solid SPMs, it is suggested that FDG-PET should be performed in the long-term follow-up of OS patients.
RESUMO
Dedifferentiated liposarcoma (DDLS) has a relatively poor prognosis, however this neoplasm rarely occurs in the head and neck. To date, no definite protocol has been established for the diagnosis and treatment of head and neck DDLS. The present study reports the case of a 69-year-old male patient with DDLS of the oral floor. To the best of our knowledge, this is the first documented case of oral floor DDLS. In addition, this is the first reported case with the development of a second primary malignancy following the treatment of head and neck DDLS. A literature review of 50 cases of head and neck DDLS revealed that preoperative biopsy is not reliable for the diagnosis of these tumors and an accurate pathological diagnosis with total resection is preferred.
RESUMO
The seed storage proteins of soybean (Glycine max) are composed mainly of glycinin (11S globulin) and ß-conglycinin (7S globulin). The subunits of glycinin (A1aB1b, A1bB2, A2B1a, A3B4, and A5A4B3) are synthesized as a single polypeptide precursor. These precursors are assembled into trimers with a random combination of subunits in the endoplasmic reticulum, and are sorted to the protein storage vacuoles. Proteins destined for transport to protein storage vacuoles possess a vacuolar sorting determinant, and in this regard, the A1aB1b subunit contains a C-terminal peptide that is sufficient for its sorting to protein storage vacuoles. The A3B4 subunit, however, lacks a corresponding C-terminal sorting determinant. In this study, we found that, unlike the A1aB1b subunit, the A3B4 subunit does not bind to previously reported vacuolar sorting receptors. Despite this difference, we observed that the A3B4 subunit is sorted to protein storage vacuoles in a transgenic soybean line expressing the A3B4 subunit of glycinin. These results indicate that a protein storage vacuolar sorting mechanism that functions independently of the known vacuolar sorting receptors in seeds might be present in soybean seeds.
Assuntos
Glycine max/metabolismo , Proteínas de Plantas/metabolismo , Sementes/metabolismo , Vacúolos/metabolismo , Sequência de Aminoácidos , Expressão Gênica , Ligantes , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Ligação Proteica , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Transporte Proteico , Proteínas Recombinantes , Glycine max/genética , Ressonância de Plasmônio de SuperfícieRESUMO
KEY MESSAGE: Mouse TGF-ß highly accumulated by expressing as a secretory homodimeric protein in transgenic rice endosperm. It was tightly deposited in ER-derived PBs by interaction with cysteine-rich prolamins. TGF-ß is one of the key players involved in the induction and maintenance of mucosal immune tolerance to dietary proteins through the induction of regulatory T cells. In order to utilize rice-based TGF-ß as a tool to promote oral immune tolerance induction, high production of TGF-ß is essentially required. When the codon-optimized mTGF-ß was expressed as a secretory protein by ligating an N-terminal signal peptide and C-terminal KDEL ER retention signal under the control of the endosperm-specific rice storage protein glutelin GluB-1 promoter, accumulation level was low in stable transgenic rice seeds. Then, to increase the accumulation level of mTGF-ß, it was expressed as fusion proteins by inserting into the C terminus of acidic subunit of glutelin GluA and the variable region of 26 kDa globulin. When fused with the glutelin, it could accumulate well as visible bands by CBB staining gel, but not for the 26 kDa globulin. Unexpectedly, expression of homodimeric mTGF-ß linked by a 6×Gly1×Ser linker as secretory protein resulted in higher level of accumulation. This expression level was further enhanced by reduction of some endogenous prolamins by RNA interference. The monomeric and dimeric mTGF-ßs were deposited in ER-derived PBs containing prolamins. When highly produced in rice seed, it is notable that most of ER-derived PBs were distorted and granulated. Step-wise extraction of storage proteins from rice seeds suggested that the mTGF-ß strongly interacted with cysteine-rich prolamins via disulfide bonds. This result was also supported by the finding that reducing agent was absolutely required for mTGF-ß extraction.
Assuntos
Oryza/genética , Sementes/genética , Fator de Crescimento Transformador beta/metabolismo , Animais , Cisteína/metabolismo , Endosperma/citologia , Endosperma/metabolismo , Endosperma/ultraestrutura , Regulação da Expressão Gênica de Plantas , Espaço Intracelular/metabolismo , Camundongos , Oryza/citologia , Oryza/ultraestrutura , Pepsina A/metabolismo , Plantas Geneticamente Modificadas , Prolaminas/química , Prolaminas/metabolismo , Multimerização Proteica , Proteínas Recombinantes/metabolismo , Sementes/citologia , Sementes/ultraestrutura , Resposta a Proteínas não DobradasRESUMO
ß-Conglycinin and glycinin are soybean major seed storage proteins. Previous studies have shown that adding the extension region of ß-conglycinin α subunit improves the emulsifying properties of proglycinin and confers more favourable characteristics than fusing the extension region of ß-conglycinin α' subunit or the hypervariable regions (A4IV) of glycinin A1aB1b subunit. To evaluate the polypeptide properties, we designed mutants of A1aB1b subunits fused with truncated versions of A4IV (A4IVcut), α (αcut) or α' (α'cut) extension regions lacking the C-terminus 25 or 31 residues (A4IVC25, αC25 or α'C31), and also A4IVcut and α'cut with αC25 residues added (A4IVcut-αC25 and α'cut-αC25). All the modified proteins displayed conformations similar to the wild type. With good solubilities, the emulsion properties of the modified proteins were much better at ionic strength µ = 0.08 than at µ = 0.5. The modified A1aB1bαcut and A1aB1bα'cut showed poorer emulsion properties than those of A1aB1bα and A1aB1bα'. Replacing the hydrophobic A4IVC25 region of A1aB1bA4IV with hydrophilic αC25 created A1aB1bA4IVcut-αC25, which had the best emulsion stability among these proglycinin mutants. We found that addition of αC25 improves the emulsifying properties of two C-terminally truncated proglycinin variants, thereby illustrating its potential general utility. Our investigation showed that in order to improve the emulsifying ability and emulsion stability of a globular protein, the introduced polypeptide should (i) be highly hydrophilic, (ii) consist of multiple hydrophobic-strong hydrophilic regions comprising at least two alpha helixes, (iii) harbour a terminal α-helix at the end of the C-terminus and (iv) have properties similar to those of αC25.
Assuntos
Antígenos de Plantas/genética , Globulinas/genética , Peptídeos/química , Proteínas de Armazenamento de Sementes/genética , Proteínas de Soja/genética , Sequência de Aminoácidos/genética , Antígenos de Plantas/química , Emulsões , Globulinas/química , Interações Hidrofóbicas e Hidrofílicas , Mutação , Peptídeos/genética , Estrutura Secundária de Proteína , Subunidades Proteicas/química , Subunidades Proteicas/genética , Proteínas de Armazenamento de Sementes/química , Proteínas de Soja/química , Glycine max/química , Glycine max/genéticaRESUMO
BACKGROUND: Reports of synchronous multiple primary cancers in patients with oral cancer have recently been increasing because of progress in radiographic diagnostic techniques. Multiple primary cancers in patients with oral cavity cancer mainly occur in the head and neck region, lung, and esophagus. 2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography is usually used to identify synchronous multiple primary cancers. CASE PRESENTATION: We herein describe a 69-year-old woman diagnosed with synchronous quadruple multiple primary cancers, namely a squamous cell carcinoma of the mobile tongue, invasive ductal carcinoma of the right breast, intraductal carcinoma of the left breast, and chromophobe renal cell carcinoma of the right kidney. We removed the four tumors over three surgical procedures to reduce the surgical risk because the patient had diabetes mellitus. To the best of our knowledge, this combination of multiple primary cancers has not been reported to date. Importantly, we followed this case for 5 years after surgery. The patient was alive and well with no clinical or radiologic signs of recurrent or metastatic disease at the time of this writing. CONCLUSIONS: In the present case, the kidney cancer could not be detected by 2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography but could be detected by contrast-enhanced computed tomography. To avoid overlooking multiple primary cancers of the kidney, we suggest that contrast-enhanced computed tomography should cover a region extending to the inferior margin of the kidney, rather than only to the liver, in patients with oral cavity cancer.
Assuntos
Neoplasias da Mama/mortalidade , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Escamosas/mortalidade , Neoplasias Renais/mortalidade , Neoplasias Primárias Múltiplas/mortalidade , Neoplasias da Língua/mortalidade , Idoso , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/cirurgia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Estadiamento de Neoplasias , Neoplasias Primárias Múltiplas/patologia , Neoplasias Primárias Múltiplas/cirurgia , Prognóstico , Taxa de Sobrevida , Neoplasias da Língua/patologia , Neoplasias da Língua/cirurgiaRESUMO
ß-Conglycinin is a major seed storage protein in soybeans, which are an important source of protein. The major subunits (α, α' and ß) of ß-conglycinin are sorted to protein-storage vacuoles in seed cells. Vacuolar sorting receptor (VSR) is an integral membrane protein that recognizes the sorting determinant of vacuolar proteins, including ß-conglycinin, and regulates their sorting process. Vacuolar sorting determinants of the α' and ß subunits of ß-conglycinin exist in their C-terminal peptides. Here, the preliminary X-ray diffraction analysis of the binding domain of soybean VSR crystallized with the peptide responsible for the sorting determinant in ß-conglycinin is reported. X-ray diffraction data were collected to a resolution of 3.5 Å. The crystals belonged to space group P3121, with unit-cell parameters a = b = 116.4, c = 86.1 Å.
Assuntos
Antígenos de Plantas/química , Globulinas/química , Glycine max/química , Receptores de Superfície Celular/química , Proteínas de Armazenamento de Sementes/química , Proteínas de Soja/química , Vacúolos/metabolismo , Cristalização , Cristalografia por Raios X , Eletroforese em Gel de Poliacrilamida , Peptídeos/química , Estrutura Terciária de Proteína , Transporte ProteicoRESUMO
There has been a significant increase in the use of transgenic plants for the large-scale production of pharmaceuticals and industrial proteins. Here, we report the stable accumulation of seed storage proteins containing disease vaccine peptides in transgenic soybean seeds. To synthesize vaccine peptides in soybean seeds, we used seed storage proteins as a carrier and a soybean breeding line lacking major seed storage proteins as a host. Vaccine peptides were inserted into the flexible disordered regions in the A1aB1b subunit three-dimensional structure. The A1aB1b subunit containing vaccine peptides in the disordered regions were sorted to the protein storage vacuoles where vaccine peptides are partially cleaved by proteases. In contrast, the endoplasmic reticulum (ER)-retention type of the A1aB1b subunit containing vaccine peptides accumulated in compartments that originated from the ER as an intact pro-form. These results indicate that the ER may be an organelle suitable for the stable accumulation of bioactive peptides using seed storage proteins as carriers.
Assuntos
Vacinas contra Alzheimer/biossíntese , Globulinas/biossíntese , Glycine max/genética , Peptídeos/imunologia , Sementes/genética , Proteínas de Soja/biossíntese , Doença de Alzheimer/imunologia , Doença de Alzheimer/prevenção & controle , Vacinas contra Alzheimer/genética , Vacinas contra Alzheimer/imunologia , Sequência de Aminoácidos , Retículo Endoplasmático/metabolismo , Expressão Gênica , Globulinas/genética , Humanos , Dados de Sequência Molecular , Mutagênese Insercional , Peptídeos/genética , Plantas Geneticamente Modificadas , Transporte Proteico , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Sementes/metabolismo , Proteínas de Soja/genética , Glycine max/metabolismo , Vacinas , Vacúolos/metabolismoRESUMO
Limited and extensive proteolysis occur when ß-conglycinin ß homo-trimer (ß(3)-conglycinin) from soybeans is attacked by papain. Slow limited proteolysis is restricted to cleavage of ß(3)-conglycinin polypeptides into subunit halves (N- and C-terminal domains) that are further slightly truncated. The kinetics of limited and extensive proteolyses analyzed separately indicates that the two processes occur independently from the very beginning of the reaction. In contrast, limited proteolysis of phaseolin from common beans has been found to be prerequisite for the onset of its extensive proteolysis. The dramatic distinction between the degradation patterns of ß(3)-conglycinin and phaseolin, homologous storage 7S globulins, suggests the existence of intrinsic differences in their structures. This hypothesis is supported by comparative analysis of the accessibilities to the solvent of amino acid residues in phaseolin and ß(3)-conglycinin structures, which indicated the relatively low packing density of the latter, resulting in enhanced susceptibility of it to extensive proteolysis.
Assuntos
Antígenos de Plantas/química , Antígenos de Plantas/metabolismo , Globulinas/química , Globulinas/metabolismo , Papaína/metabolismo , Multimerização Proteica , Proteólise , Proteínas de Armazenamento de Sementes/química , Proteínas de Armazenamento de Sementes/metabolismo , Proteínas de Soja/química , Proteínas de Soja/metabolismo , Sequência de Aminoácidos , Hidrólise , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Peso Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Estrutura Quaternária de Proteína , Glycine max , Especificidade por SubstratoRESUMO
Glycinin is one of the most abundant storage-protein molecules in soybean seeds and is composed of five subunits (A1aB1b, A1bB2, A2B1a, A3B4 and A5A4B3). A1bB2 was purified from a mutant soybean cultivar containing glycinin composed of only A5A4B3 and A1bB2. At 281 K the protein formed hexagonal, rectangular and rod-shaped crystals in the first [0.1 M imidazole pH 8.0, 0.2 M MgCl2, 35%(v/v) MPD], second [0.1 M sodium citrate pH 5.6, 0.2 M ammonium acetate, 30%(v/v) MPD] and third (0.1 M phosphate-citrate pH 4.2, 2.0 M ammonium sulfate) crystallization conditions, respectively. X-ray diffraction data were collected to resolutions of 1.85, 1.85 and 2.5 Å from crystals of the three different shapes. The crystals belonged to space groups P6322, P21 and P1, with unit-cell parameters a = b = 143.60, c = 84.54 Å, a = 114.54, b = 105.82, c = 116.67 Å, ß = 94.99° and a = 94.45, b = 94.96, c = 100.66 Å, α = 107.02, ß = 108.44, γ = 110.71°, respectively. One, six and six subunits of A1bB2 were estimated to be present in the respective asymmetric units. The three-dimensional structure of the A1bB2 hexamer is currently being determined.
Assuntos
Globulinas/química , Globulinas/isolamento & purificação , Glycine max , Proteínas de Soja/química , Proteínas de Soja/isolamento & purificação , Cristalização , Cristalografia por Raios X , Globulinas/genética , Mutação/genética , Proteínas de Soja/genéticaRESUMO
A photo-switchable fluorescent flagging approach has been developed to identify photoaffinity-labeled peptides in target protein. Upon photochemical release of the ligand, the protein was newly modified with a coumarin in place of the previously attached biotin. It allowed us to simplify complex identification processes for labeled sites.
Assuntos
Cumarínicos/química , Peptídeos/química , Marcadores de Fotoafinidade/química , Proteínas de Transporte Vesicular/química , Sítios de Ligação , Ligantes , Estrutura Molecular , Glycine max/químicaRESUMO
Oleosins contain a unique hydrophobic domain which is inserted into the oil matrix and are involved in the formation and stability of plant oil bodies. These proteins have also been reported to possess some allergenic properties. Therefore, knowledge of its three-dimensional structure is vital for further structural and immunological characterization. However, due to the difficulty of soluble recombinant expression in Escherichia coli, no studies have been done in line with this goal. Here, we have developed a novel expression and purification system for three peanut oleosin isoforms (14 k, 16 k, and 18 kDa oleosins). Oleosin cDNAs were cloned and subsequently expressed in soluble form in insect cell-baculovirus system. Recombinant proteins can be purified to homogeneity using only Ni Sepharose affinity chromatography. Thermal denaturation midpoint temperatures of recombinant oleosins were also assayed and found to be very similar to that of native oleosins, indicating proper structural conformation of the recombinant proteins.