Preprint Article Version 1 NOT YET PEER-REVIEWED

Perturbation Analysis of Calcium, Alkalinity and Secretion during Growth of Lily Pollen Tubes

  1. School of Natural Science, Hampshire College, Amherst, MA 01002, USA
  2. Biology Department, University of Massachusetts, Amherst, MA 01003, USA
Version 1 : Received: 31 October 2016 / Approved: 1 November 2016 / Online: 1 November 2016 (05:25:42 CET)

How to cite: Winship, L.; Rounds, C.; Hepler, P. Perturbation Analysis of Calcium, Alkalinity and Secretion during Growth of Lily Pollen Tubes. Preprints 2016, 2016110003 (doi: 10.20944/preprints201611.0003.v1). Winship, L.; Rounds, C.; Hepler, P. Perturbation Analysis of Calcium, Alkalinity and Secretion during Growth of Lily Pollen Tubes. Preprints 2016, 2016110003 (doi: 10.20944/preprints201611.0003.v1).

Abstract

Pollen tubes grow by spatially and temporally regulated expansion of new material secreted into the cell wall at the tip of the tube. A complex web of interactions among cellular components, ions and small molecule provides dynamic control of localized expansion and secretion. Cross-correlation studies on oscillating lily (Lilium formosanum Wallace) pollen tubes showed that an increase in intracellular calcium follows an increase in growth, whereas the increase in the alkaline band and in secretion both anticipate the increase in growth rate. Calcium, as a follower, is unlikely to be a stimulator of growth, whereas the alkaline band, as a leader, may be an activator. To gain further insight herein we reversibly inhibited growth with potassium cyanide (KCN), and followed the re-establishment of calcium, pH and secretion patterns as growth resumed. While KCN markedly slows growth and causes the associated gradients of calcium and pH to sharply decline, its removal allows growth and vital processes to fully recover. The calcium gradient reappears before growth restarts, however it is preceded by both the alkaline band and secretion, in which the alkaline band is slightly advanced over secretion. Thus the pH gradient, rather than the tip-focused calcium gradient, may regulate pollen tube growth.

Subject Areas

calcium; protons; exocytosis; tip growth; Lilium; pollen; respiration; perturbation analysis

Readers' Comments and Ratings (0)

Discuss and rate this article
Views 95
Downloads 74
Comments 0
Metrics 0
Discuss and rate this article

×
Alerts
Notify me about updates to this article or when a peer-reviewed version is published.