Development of root nodules of mung bean (Vigna radiata): a reinvestigation of endocytosis

1981 ◽  
Vol 59 (12) ◽  
pp. 2478-2499 ◽  
Author(s):  
William Newcomb ◽  
Laurel McIntyre

The release of rhizobia from infection threads of mung bean (Vigna radiata) root nodules is an endocytotic process. The peribacteroid membrane surrounding the released bacteria is initially derived from the host plasma membrane which surrounds the infection thread and not from the nuclear envelope as previously reported by Prasad and De. Endoplasmic reticulum (ER) profiles and Golgi vesicles fuse with the infection thread cell wall and adjacent host plasma membrane. Although some ER profiles were continuous with the outer membrane of the nuclear envelope, no continuities of the nuclear envelope with the infection thread, the host plasma membrane, or the peribacteroid membrane were observed. Furthermore, no blebbing of the nuclear envelope was observed.

1978 ◽  
Vol 78 (3) ◽  
pp. 919-936 ◽  
Author(s):  
D P Verma ◽  
V Kazazian ◽  
V Zogbi ◽  
A K Bal

The membrane envelope enclosing the bacteroids in soybean root nodules is shown by ultrastructural and biochemical studies to be derived from, and to retain the characteristics of, the host cell plasma membrane. During the early stages of the infection process, which occurs through an invagination, Rhizobium becomes surrounded by the host cell wall and plasma membrane, forming the infection thread. The cell wall of the infection thread is degraded by cellulolytic enzyme(s), leaving behind the enclosed plasma membrane, the membrane envelope. Cellulase activity in young nodules increases two- to threefold as compared to uninfected roots, and this activity is localized in the cell wall matrix of the infection threads. Membrane envelopes were isolated by first preparing bacteroids enclosed in the envelopes on a discontinuous sucrose gradient followed by passage through a hypodermic needle, which released the bacteroids from the membranes. This membrane then sedimented at the interface of 34--45% sucrose (mean density of 1.14 g/cm3). Membranes were characterized by phosphotungstic acid (PTA)-chromic acid staining. ATPase activity, and localization, sensitivity to nonionic detergent Nonidet P-40 (NP-40) and sodium dodecyl sulfate (SDS) gel electrophoresis. These analyses revealed a close similarity between plasma membrane and the membrane envelope. Incorporation of radioactive amino acids into the membrane envelope proteins was sensitive to cycloheximide, suggesting that the biosynthesis of these proteins is primarily under host-cell control. No immunoreactive material to leghemoglobin antibodies was found inside or associated with the isolated bacteroids enclosed in the membrane envelope, and its location is confined to the host cell cytoplasmic matrix.


1981 ◽  
Vol 59 (9) ◽  
pp. 1547-1552 ◽  
Author(s):  
William Newcomb ◽  
Susan Creighton ◽  
Lenore Latta

A transmission electron microscopic study of nodules of Vicia faba has demonstrated that rhizobia are released from the infection threads by an endocytotic process. The rhizobia escape from unwalled regions of the infection thread or unwalled droplets of thread matrix and upon escape are surrounded by a peribacteroid membrane which is derived from the plasma membrane bounding the unwalled regions of thread matrix. Thus, the release of bacteria in V. faba nodules is essentially identical to that reported in other leguminous nodules and the peribacteroid membrane does not arise de novo as previously reported by other workers.


1979 ◽  
Vol 57 (4) ◽  
pp. 315-323 ◽  
Author(s):  
Glenn Wehtje ◽  
Larry J. Littlefield ◽  
David E. Zimmer

Penetration of sunflower, Heliantluis animus, root epidermal cells by zoospores of Plasmopara halstedii is preceded by formation of a papilla on the inner surface of the host cell wall that invaginates the host plasma membrane. Localized degradation and penetration of the host cell wall by the pathogen follow. The invading fungus forms an allantoid primary infection vesicle in the penetrated epidermal cell. The host plasma membrane invaginates around the infection vesicle but its continuity is difficult to follow. Upon exit from the epidermal cell the fungus may grow intercellularly, producing terminal haustorial branches which extend into adjacent host cells. The fungus may grow through one or two cortical cell is after growing from the epidermal cell before it becomes intercellular. Host plasma membrane is not penetrated by haustoria. Intercellular hyphae grow toward the apex of the plant and ramify the seedling tissue. Resistance in an immune cultivar is hypersensitive and is triggered upon contact of the host cell with the encysting zoospore before the host cell wall is penetrated. Degeneration of zoospore cytoplasm accompanies the hypersensitive reaction of the host. Zoospores were often parasitized by bacteria and did not germinate unless penicillin and streptomycin were added to the inoculum suspension.


1986 ◽  
Vol 32 (12) ◽  
pp. 947-952 ◽  
Author(s):  
Shiro Higashi ◽  
Kazuya Kushiyama ◽  
Mikiko Abe

The morphological characteristics of infection threads in the root nodules of Astragalus sinicus were examined by scanning and transmission electron microscopy. The infection threads, epidermal cell walls, and vascular bundles of the nodule were not altered when a nodule was treated with driselase (a plant cell wall degrading enzyme), although the cell walls of meristematic and bacteroid-including zones were completely decomposed by the enzyme treatment. Some infection threads were funnel shaped at the site of attachment of the infection thread to the host cell wall.


1985 ◽  
Vol 78 (4) ◽  
pp. 665-672 ◽  
Author(s):  
Eduardo Blumwald ◽  
Marc G. Fortin ◽  
Philip A. Rea ◽  
Desh Pal S. Verma ◽  
Ronald J. Poole

2011 ◽  
Vol 75 (1) ◽  
pp. 33-38 ◽  
Author(s):  
Marzena Sujkowska ◽  
Wojciech Borucki ◽  
Władysław Golinowski

Changes in the activity of acid phosphatase (AcPase) in the apoplast of pea root nodule were investigated. The activity was determined using lead and cerium methods. The results indicated a following sequence of AcPase activity appearance during the development of the infection thread: 1) low AcPase activity appears in the outer part of cells of symbiotic bacteria; 2) bacteria show increased AcPase activity, and the enzyme activity appears in the thread walls; 3) activity exhibits also matrix of the infection thread; 4) bacteria just before their release from the infection threads show high AcPase activity; 5) AcPase activity ceases after bacteria transformation into bacteroids. The increase in bacterial AcPase activity may reflect a higher demand for inorganic phosphorus necessary for propagation of the bacteria within the infection threads and/or involved in bacteria release from the infection threads.


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