ISSN:
1615-6102
Keywords:
Pollen wall
;
Exine subunits
;
Ubisch bodies
;
Sporopollenin
;
Freeze substitution
;
Pectin immunocytochemistry
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary High-pressure freezing/freeze substitution/TEM was employed to investigate anthers of the monocotyledonous angiospermLedebouria socialis Roth (Hyacinthaceae) during early tetrad stage. The initials of the outer sporopollenous pollen wall stratum (=sexine) and of the homologous tapetal products (=Ubisch bodies) are composed of highly regular subunits: clustered globules with a constant diameter of approximately 28 nm. The clusters develop within diffuse accumulations of electron-dense material. This process, interpreted as sporopollenin polymerization, does not necessarily depend on the presence of membrane-bound enzymes. Immunogold labeling with JIM 5 and JIM 7 antibodies revealed that the primexine as well as the dissolving tapetal cell walls, the sites of sexine and Ubisch body formation, respectively, contain un-esterified and methyl-esterified pectins.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01403683
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