CYTOCHEMICAL AND DEVELOPMENTAL CHANGES IN MICROBODIES (GLYOXYSOMES) AND RELATED ORGANELLES OF CASTOR BEAN ENDOSPERM

Structural changes in endosperm cells of germinating castor beans were examined and complemented with a cytochemical analysis of staining with diaminobenzidine (DAB). Deposition of oxidized DAB occurred only in microbodies due to the presence of catalase, and in cell walls associated with peroxidase activity. Seedling development paralleled the disappearance of spherosomes (lipid bodies) and matrix of aleurone grains in endosperm cells. 6 to 7 days after germination, a cross-section through the endosperm contained cells in all stages of development and senescence beginning at the seed coat and progressing inward to the cotyledons. Part of this aging process involved vacuole formation by fusion of aleurone grain membranes. This coincided with an increase in microbodies (glyoxsomes), mitochondria, plastids with an elaborate tubular network, and the formation of a new protein body referred to as a dilated cisterna, which is structurally and biochemically distinct from microbodies although both apparently develop from rough endoplasmic reticulum (ER). In vacuolate cells microbodies are the most numerous organelle and are intimately associated with spherosomes and dilated cisternae. This phenomenon is discussed in relation to the biochemical activities of these organelles. Turnover of microbodies involves sequestration into autophagic vacuoles as intact organelles which still retain catalase activity. Crystalloids present in microbodies develop by condensation of matrix protein and are the principal site of catalase formerly in the matrix.

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Periodic Structure in the Matrix Protein of an Insect Virus

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100054121 ◽

1982 ◽

Vol 40 ◽

pp. 302-303

Author(s):

H.M. Mazzone ◽

W.F. Engler ◽

R. Zerillo ◽

G.F. Bahr

Keyword(s):

Inclusion Body ◽

Periodic Structure ◽

Matrix Protein ◽

Malacosoma Disstria ◽

Insect Virus ◽

Virus Particles ◽

The Matrix ◽

Nucleopolyhedrosis Virus

The nucleopolyhedrosis virus (NPV) of the forest tent cater - pillar (Malacosoma disstria Hubner) has been analyzed in our laboratories. As a representative of the Baculovirus class, the NPV has virus particles enclosed with in a proteinaceous structure, the inclusion body.

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Overview of Popular Techniques of Raman Spectroscopy and Their Potential in the Study of Plant Tissues

Molecules ◽

10.3390/molecules26061537 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1537

Author(s):

Aneta Saletnik ◽

Bogdan Saletnik ◽

Czesław Puchalski

Keyword(s):

Raman Spectroscopy ◽

Cell Walls ◽

Structural Changes ◽

Spatial Information ◽

Technological Development ◽

Analytical Techniques ◽

High Sensitivity ◽

Plant Tissues ◽

Wide Range ◽

Identification Technique

Raman spectroscopy is one of the main analytical techniques used in optical metrology. It is a vibration, marker-free technique that provides insight into the structure and composition of tissues and cells at the molecular level. Raman spectroscopy is an outstanding material identification technique. It provides spatial information of vibrations from complex biological samples which renders it a very accurate tool for the analysis of highly complex plant tissues. Raman spectra can be used as a fingerprint tool for a very wide range of compounds. Raman spectroscopy enables all the polymers that build the cell walls of plants to be tracked simultaneously; it facilitates the analysis of both the molecular composition and the molecular structure of cell walls. Due to its high sensitivity to even minute structural changes, this method is used for comparative tests. The introduction of new and improved Raman techniques by scientists as well as the constant technological development of the apparatus has resulted in an increased importance of Raman spectroscopy in the discovery and defining of tissues and the processes taking place in them.

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Methods to extract the exopolymeric matrix from biofilms: a comparative study

Water Science & Technology ◽

10.2166/wst.1999.0365 ◽

1999 ◽

Vol 39 (7) ◽

pp. 243-250 ◽

Cited By ~ 19

Author(s):

Joana Azeredo ◽

Valentina Lazarova ◽

Rosário Oliveira

Keyword(s):

Organic Carbon ◽

Comparative Study ◽

Mixed Culture ◽

Pure Culture ◽

Cell Walls ◽

Extraction Method ◽

Extraction Methods ◽

Suitable Method ◽

The Matrix ◽

Biofilm Matrix

To study the composition of a biofilm a previous extraction method is required to separate cells from the matrix. There are several methods reported in the literature; however they are not efficient or promote leakage of intracellular material. In this work several extraction methods were assayed in mixed culture and pure culture biofilms and their efficiency was evaluated by the amount of organic carbon, proteins and intracellular material extracted. The results showed that the extraction with glutaraldehyde 3% (w/v) was the most suitable method, extracting great amounts of organic carbon without promoting cell lysis or permeabilization. Glutaraldehyde is a bifunctional reagent that binds to cell walls avoiding their permeabilization and the biofilm matrix is solubilized in the solution.

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Characterization of Mmp37p, aSaccharomyces cerevisiaeMitochondrial Matrix Protein with a Role in Mitochondrial Protein Import

Molecular Biology of the Cell ◽

10.1091/mbc.e06-04-0366 ◽

2006 ◽

Vol 17 (9) ◽

pp. 4051-4062 ◽

Cited By ~ 47

Author(s):

Michelle R. Gallas ◽

Mary K. Dienhart ◽

Rosemary A. Stuart ◽

Roy M. Long

Keyword(s):

Matrix Protein ◽

Protein Import ◽

Mitochondrial Protein ◽

Temperature Sensitive ◽

Inner Membrane ◽

Mitochondrial Inner Membrane ◽

Close Proximity ◽

The Matrix ◽

Targeting Signal

Many mitochondrial proteins are encoded by nuclear genes and after translation in the cytoplasm are imported via translocases in the outer and inner membranes, the TOM and TIM complexes, respectively. Here, we report the characterization of the mitochondrial protein, Mmp37p (YGR046w) and demonstrate its involvement in the process of protein import into mitochondria. Haploid cells deleted of MMP37 are viable but display a temperature-sensitive growth phenotype and are inviable in the absence of mitochondrial DNA. Mmp37p is located in the mitochondrial matrix where it is peripherally associated with the inner membrane. We show that Mmp37p has a role in the translocation of proteins across the mitochondrial inner membrane via the TIM23-PAM complex and further demonstrate that substrates containing a tightly folded domain in close proximity to their mitochondrial targeting sequences display a particular dependency on Mmp37p for mitochondrial import. Prior unfolding of the preprotein, or extension of the region between the targeting signal and the tightly folded domain, relieves their dependency for Mmp37p. Furthermore, evidence is presented to show that Mmp37 may affect the assembly state of the TIM23 complex. On the basis of these findings, we hypothesize that the presence of Mmp37p enhances the early stages of the TIM23 matrix import pathway to ensure engagement of incoming preproteins with the mtHsp70p/PAM complex, a step that is necessary to drive the unfolding and complete translocation of the preprotein into the matrix.

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Signaling Mechanisms in the Regulation of Renal Matrix Metabolism in Diabetes

Experimental Diabetes Research ◽

10.1155/2012/749812 ◽

2012 ◽

Vol 2012 ◽

pp. 1-10 ◽

Cited By ~ 23

Author(s):

Meenalakshmi M. Mariappan

Keyword(s):

Extracellular Matrix ◽

Signaling Pathways ◽

Matrix Protein ◽

Structural Changes ◽

Mammalian Target Of Rapamycin ◽

Adverse Outcomes ◽

Matrix Proteins ◽

Extracellular Matrix Protein ◽

Renal Hypertrophy ◽

Matrix Metabolism

Renal hypertrophy and accumulation of extracellular matrix proteins are among cardinal manifestations of diabetic nephropathy. TGF beta system has been implicated in the pathogenesis of these manifestations. Among signaling pathways activated in the kidney in diabetes, mTOR- (mammalian target of rapamycin-)regulated pathways are pivotal in orchestrating high glucose-induced production of ECM proteins leading to functional and structural changes in the kidney culminating in adverse outcomes. Understanding signaling pathways that influence individual matrix protein expression could lead to the development of new interventional strategies. This paper will highlight some of the diverse components of the signaling network stimulated by hyperglycemia with an emphasis on extracellular matrix protein metabolism in the kidney in diabetes.

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Ionic selectivity of pores formed by the matrix protein (porin) of Escherichia coli

Biochimica et Biophysica Acta (BBA) - Biomembranes ◽

10.1016/0005-2736(89)90002-3 ◽

1979 ◽

Vol 551 (2) ◽

pp. 238-247 ◽

Cited By ~ 216

Author(s):

R. Benz ◽

K. Janko ◽

P. Läuger

Keyword(s):

Escherichia Coli ◽

Matrix Protein ◽

Ionic Selectivity ◽

The Matrix

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Mitochondrial Lon protease is a gatekeeper for proteins newly imported into the matrix

Communications Biology ◽

10.1038/s42003-021-02498-z ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Yuichi Matsushima ◽

Kazuya Takahashi ◽

Song Yue ◽

Yuki Fujiyoshi ◽

Hideaki Yoshioka ◽

...

Keyword(s):

Protease Activity ◽

Matrix Protein ◽

Protein Import ◽

Atp Hydrolysis ◽

Lon Protease ◽

Mitochondrial Matrix ◽

The Matrix ◽

Specific Proteins ◽

Aggregation Activity ◽

Hydrolysis Activity

AbstractHuman ATP-dependent Lon protease (LONP1) forms homohexameric, ring-shaped complexes. Depletion of LONP1 causes aggregation of a broad range of proteins in the mitochondrial matrix and decreases the levels of their soluble forms. The ATP hydrolysis activity, but not protease activity, of LONP1 is critical for its chaperone-like anti-aggregation activity. LONP1 forms a complex with the import machinery and an incoming protein, and protein aggregation is linked with matrix protein import. LONP1 also contributes to the degradation of imported, aberrant, unprocessed proteins using its protease activity. Taken together, our results show that LONP1 functions as a gatekeeper for specific proteins imported into the mitochondrial matrix.

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Homocysteine and Hypertension in Diabetes: Does PPARγHave a Regulatory Role?

PPAR Research ◽

10.1155/2010/806538 ◽

2010 ◽

Vol 2010 ◽

pp. 1-12 ◽

Cited By ~ 23

Author(s):

Utpal Sen ◽

Suresh C. Tyagi

Keyword(s):

Matrix Protein ◽

Vascular Endothelial Cells ◽

Tissue Inhibitor Of Metalloproteinase ◽

Extracellular Matrix Protein ◽

Matrix Remodeling ◽

Renal Volume ◽

Vascular Effects ◽

Beneficial Effects ◽

The Matrix ◽

Volume Retention

Dysfunction of macro- and microvessels is a major cause of morbidity and mortality in patients with cardio-renovascular diseases such as atherosclerosis, hypertension, and diabetes. Renal failure and impairment of renal function due to vasoconstriction of the glomerular arteriole in diabetic nephropathy leads to renal volume retention and increase in plasma homocysteine level. Homocysteine, which is a nonprotein amino acid, at elevated levels is an independent cardio-renovascular risk factor. Homocysteine induces oxidative injury of vascular endothelial cells, involved in matrix remodeling through modulation of the matrix metalloproteinase (MMP)/tissue inhibitor of metalloproteinase (TIMP) axis, and increased formation and accumulation of extracellular matrix protein, such as collagen. In heart this leads to increased endothelial-myocyte uncoupling resulting in diastolic dysfunction and hypertension. In the kidney, increased matrix accumulation in the glomerulus causes glomerulosclerosis resulting in hypofiltration, increased renal volume retention, and hypertension. PPARγagonist reduces tissue homocysteine levels and is reported to ameliorate homocysteine-induced deleterious vascular effects in diabetes. This review, in light of current information, focuses on the beneficial effects of PPARγagonist in homocysteine-associated hypertension and vascular remodeling in diabetes.

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