Skip Navigation

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by HESLOP-HARRISON, J.
Right arrow Articles by HOWLETT, B.
Right arrow Search for Related Content
PubMed
Right arrow Articles by HESLOP-HARRISON, J.
Right arrow Articles by HOWLETT, B.
Agricola
Right arrow Articles by HESLOP-HARRISON, J.
Right arrow Articles by HOWLETT, B.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Annals of Botany 37: 403-412, 1973
© 1973 Annals of Botany Company

RESEARCH-ARTICLE

Pollen-wall Proteins: ‘Gametophytic’ and ‘Sporophytic’ Fractions in the Pollen Walls of the Malvaceae

J. HESLOP-HARRISON1, Y. HESLOP-HARRISON1, R. B. KNOX2 and B. HOWLETT2

1Royal Botanic Gardens Kew, Richmond, Surrey
2Botany Department, Australian National University Canberra

Received: 20 October 1972   

Proteins are stored in two sites in the pollen grain walls of the Malvaceae, (a) in the cellulosic intine, mainly in the vicinity of the circular apertures, and (b) in cavities in the sculptured layer of the exine. The intine-held materials are incorporated during the growth of the wall. The exine materials are derived from the tapetum, which during dissolution releases cistemae with a granular-fibrillar content bounded by ribosomal membranes. This fraction is injected into the exine cavities after the completion of wall growth through micropores in the tectum. PAS-reacting material is associated with the injected protein. Another tapetal fraction, lipid in nature and commonly containing carotenoids, remains on the surface of the pollen grains to form the Pollenkitt.

While protein can be detected cytochemically in both intine and exine sites, acid phosphatase and ribonuclease activity was found to be associated only with the former. Immunofluorescence methods using antiserum to total pollen leachates showed that antigens are present in both sites.

When the pollen grains are moistened, the exine-held proteins begin to pass out through the micro-pores in the tectum within 30 s of moistening, while the main discharge from the apertural intine follows in 4–5 min.

These observations, together with evidence from other families, suggest that the intine-held proteins of angiosperm pollen grains are always produced by the male gametophyte, while those held in exine cavities are sporophytic in origin, being derived from the tapetum. As previously proposed, it seems probable that in intraspecific incompatibility systems of the gametophytic type control is mediated through intine-held ‘recognition substances’, whereas in sporophytic systems the exine-held materials are concerned.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer:
Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.