scholarly journals Differential distribution of xyloglucan glycosyl transferases in pea Golgi dictyosomes and secretory vesicles

1990 ◽  
Vol 96 (4) ◽  
pp. 705-710
Author(s):  
DAVID A. BRUMMELL ◽  
ANNE CAMIRANDE ◽  
GORDON A. MACLACHLAN
Keyword(s):  
Cell Wall ◽  
Pisum Sativum ◽  
Golgi Apparatus ◽  
Membrane Preparation ◽  
Transferase Activity ◽  
Side Chains ◽  
Secretory Vesicles ◽  
Differential Distribution ◽  
Microsomal Membranes ◽  
Isopycnic Centrifugation

Rate-zonal centrifugation of pea (Pisum sativum var. Alaska) stem microsomal membranes on a linear Renografln gradient separated Golgi secretory vesicles from dictyosomes. Secretory vesicles possessed high levels of xyloglucan fucosyl transferase activity, which effects the final decoration of stem xyloglucan side-chains, but lacked substantial xyloglucan xylosyl transferase activity, which is required for the synthesis of the xyloglucan backbone. In contrast, total dictyosomal membranes possessed both fucosyl and xylosyl transferase activities. Isopycnic centrifugation of a homogenized dictyosome-enriched membrane preparation on a shallower Renografln gradient indicated that lighter dictyosomal membranes possessed xylosyl transferase but relatively little fucosyl transferase activity. The bulk of the dictyosomal membranes formed a denser peak in which xylosyl and fucosyl transferase activities codistributed. Thus a differential localization of function in the Golgi apparatus during biosynthesis of xyloglucan is indicated. A tentative mechanism is suggested in which the elaboration of the glucose-xylose backbone is initiated in lighter dictyosomal membranes, backbone synthesis is concluded and fucosylation begun in denser dictyosomal membranes, and fucosylation completed in Golgi secretory vesicles during transport of xyloglucan to the cell wall.

Observations of the Golgi Apparatus in Pisum Primary Roots

1968 ◽  
Vol 26 ◽  
pp. 14-15
Author(s):  
Gordon C. Spink
Keyword(s):  
Cell Wall ◽  
Plasma Membrane ◽  
Pisum Sativum ◽  
Golgi Apparatus ◽  
Common Garden ◽  
Root Tip ◽  
Garden Pea ◽  
Wall Area ◽  
Primary Roots ◽  
Columella Cells

It is known that the product of the Golgi apparatus vesicles is deposited at and localized in the cell wall. This is accomplished by the formation of the hypertrophied dictyosomes and the subsequent movement of these vesicles to the plasma membrane (Fig. 1). After fusion with the plasma membrane, the secreted material is released into the cell wall area and, in some plants under appropriate conditions, moves outward through the cell wall and appears as a droplet on the root tip.In primary roots of Pisum sativum, var. Alaska (common garden pea) the Golgi apparatus vesicle product accumulates between the plasma membrane and the cell wall, particularly in those cells at the extreme tip of the root. These cells are formed at the acropetal end of the columella cells.

scholarly journals Spatial organization of the assembly pathways of glycoproteins and complex polysaccharides in the Golgi apparatus of plants.

1991 ◽  
Vol 112 (4) ◽  
pp. 589-602 ◽  
Author(s):  
P J Moore ◽  
K M Swords ◽  
M A Lynch ◽  
L A Staehelin
Keyword(s):  
Cell Wall ◽  
Golgi Apparatus ◽  
Indirect Evidence ◽  
Root Tip ◽  
Secretory Vesicles ◽  
Pectic Polysaccharide ◽  
Trans Golgi Network ◽  
Golgi Network ◽  
In Cis ◽  
Assembly Pathways

The Golgi apparatus of plant cells is the site of assembly of glycoproteins, proteoglycans, and complex polysaccharides, but little is known about how the different assembly pathways are organized within the Golgi stacks. To study these questions we have employed immunocytochemical techniques and antibodies raised against the hydroxyproline-rich cell wall glycoprotein, extensin, and two types of complex polysaccharides, an acidic pectic polysaccharide known as rhamnogalacturonan I (RG-I), and the neutral hemicellulose, xyloglucan (XG). Our micrographs demonstrate that individual Golgi stacks can process simultaneously glycoproteins and complex polysaccharides. O-linked arabinosylation of the hydroxyproline residues of extensin occurs in cis-cisternae, and glycosylated molecules pass through all cisternae before they are packaged into secretory vesicles in the monensin-sensitive, trans-Golgi network. In contrast, in root tip cortical parenchyma cells, the anti-RG-I and the anti-XG antibodies are shown to bind to complementary subsets of Golgi cisternae, and several lines of indirect evidence suggest that these complex polysaccharides may also exit from different cisternae. Thus, RG-I type polysaccharides appear to be synthesized in cis- and medial cisternae, and have the potential to leave from a monensin-insensitive, medial cisternal compartment. The labeling pattern for XG suggests that it is assembled in trans-Golgi cisternae and departs from the monensin-sensitive trans-Golgi network. This physical separation of the synthesis/secretion pathways of major categories of complex polysaccharides may prevent the synthesis of mixed polysaccharides, and provides a means for producing secretory vesicles that can be targeted to different cell wall domains.

Golgi Apparatus Secretion of Vacuolar Substances in Maize Root Cells

1976 ◽  
Vol 34 ◽  
pp. 44-45
Author(s):  
H. H. Mollenhauer ◽  
J. E. Hanson
Keyword(s):  
Cell Wall ◽  
Golgi Apparatus ◽  
Mammalian Cells ◽  
Secretory Vesicle ◽  
General Mechanism ◽  
Secretory Vesicles ◽  
Extracellular Medium ◽  
Root Cells ◽  
Ultrastructural Studies ◽  
Secretory Products

It has long been known that secretory vesicles from the Golgi apparatus discharge their contents through the plasmalemma by a process of membrane fusion called exocytosis (2,3). Ultrastructural studies have shown that the membrane of the secretory vesicle fuses with the plasmalemma, opens up at the site of fusion, and then discharges the vesicle product to the extracellular medium (i.e., to the lumen or cell wall) (2,3). Exocytosis is recognized as a widely occurring, and possibly general, mechanism for the discharge of macromolecular secretory products (2,3). A similar mechanism is also operable for the transfer of Golgi apparatus product into the acrosome (a lysosome) of mammalian cells (4).

Correlated Changes Between the Golgi Apparatus and Cell Wall Formation During Sporogenesis

1967 ◽  
Vol 25 ◽  
pp. 80-81
Author(s):  
John E. Ridgway
Keyword(s):  
Cell Wall ◽  
Plasma Membrane ◽  
Golgi Apparatus ◽  
Electron Density ◽  
Intimate Relationship ◽  
Wall Layer ◽  
Secretory Vesicles ◽  
Cell Wall Formation ◽  
Layer I ◽  
Cell Wall Deposition

During the formation of cell wall layers of the sporocyte and spore during sporogenesis in Anthoceros fuciformis Mont., there appears to he an intimate relationship between the Golgi apparatus and cell wall deposition. As the initial sporocyte wall if formed, the cisternae of the Golgi apparatus become extensively hypertrophied and produce large vesicles which move through the cytoplasm and empty their contents through the plasma membrane to form the developing primary sporocyte wall layer (I) (Figure 1). In both methods of fixation used, a similiar electron density was observed in the contents of the Golgi cisternae, the Golgi secretory vesicles, and the components of the sporocyte wall layer-I.

Cephalothin v. cephaloridine

1969 ◽  
Vol 7 (26) ◽  
pp. 101-102
Keyword(s):  
Cell Wall ◽  
Side Chains ◽  
Cell Wall Synthesis

Cephalosporin compounds, like the penicillins, act by inhibiting cell wall synthesis in multiplying bacteria. By attaching different side chains to the 7-aminocephalosporanic acid nucleus, a number of different cephalosporins have been produced. The first drug of the group to be introduced in Britain was cephaloridine (Ceporin - Glaxo), which we discussed in 1965.1 Now another compound, cephalothin (Keflin - Lilly) has become available. It has been used in the U.S.A. since 1963, and much of the information about it comes from American work. Very recently a third cephalosporin has been introduced, cephalexin (Ceporex - Glaxo; Keflex - Lilly). Its most important feature is that it is active by mouth. We shall discuss it in a forthcoming issue.

Concomitant synthesis and attachment of cell wall polymers by a membrane preparation from Micrococcus varians ATCC 29750

1980 ◽  
Vol 9 (1) ◽  
pp. 55-62 ◽  
Author(s):  
H.A.I. McArthur ◽  
F.M. Roberts ◽  
I.C. Hancock ◽  
J. Baddiley
Keyword(s):  
Cell Wall ◽  
Membrane Preparation ◽  
Cell Wall Polymers

scholarly journals Yeast actin cytoskeleton mutants accumulate a new class of Golgi-derived secretary vesicle.

1997 ◽  
Vol 8 (8) ◽  
pp. 1481-1499 ◽  
Author(s):  
J Mulholland ◽  
A Wesp ◽  
H Riezman ◽  
D Botstein
Keyword(s):  
Cell Wall ◽  
Plasma Membrane ◽  
Actin Cytoskeleton ◽  
Biochemical Analysis ◽  
Small Gtpase ◽  
Secretory Vesicles ◽  
Cytoskeleton Organization ◽  
New Class ◽  
Actin Cytoskeleton Organization ◽  
Vectorial Transport

Many yeast actin cytoskeleton mutants accumulate large secretory vesicles and exhibit phenotypes consistent with defects in polarized growth. This, together with actin's polarized organization, has suggested a role for the actin cytoskeleton in the vectorial transport of late secretory vesicles to the plasma membrane. By using ultrastructural and biochemical analysis, we have characterized defects manifested by mutations in the SLA2 gene (also known as the END4 gene), previously found to affect both the organization of the actin cytoskeleton and endocytosis in yeast. Defects in cell wall morphology, accumulated vesicles, and protein secretion kinetics were found in sla2 mutants similar to defects found in act1 mutants. Vesicles that accumulate in the sla2 and act1 mutants are immunoreactive with antibodies directed against the small GTPase Ypt1p but not with antibodies directed against the homologous Sec4p found on classical "late" secretory vesicles. In contrast, the late-acting secretory mutants sec1-1 and sec6-4 are shown to accumulate anti-Sec4p-positive secretory vesicles as well as vesicles that are immunoreactive with antibodies directed against Ypt1p. The late sec mutant sec4-8 is also shown to accumulate Ypt1p-containing vesicles and to exhibit defects in actin cytoskeleton organization. These results indicate the existence of at least two classes of morphologically similar, late secretory vesicles (associated with Ypt1p+ and Sec4p+, respectively), one of which appears to accumulate when the actin cytoskeleton is disorganized.

Distribution of antigenic oligomannosyl side chains in the cell wall mannans of several strains of Candida tropicalis

2003 ◽  
Vol 180 (1) ◽  
pp. 76-80 ◽  
Author(s):  
Hidemitsu Kobayashi ◽  
Hiroko Oyamada ◽  
Kyoko Matsuda ◽  
Nobuyuki Shibata ◽  
Shigeo Suzuki
Keyword(s):  
Cell Wall ◽  
Candida Tropicalis ◽  
Side Chains
Sign in / Sign up

Export Citation Format

Share Document