Planta

, Volume 221, Issue 3, pp 406–416

Comparative analysis of expressed sequence tags from cold-acclimated and non-acclimated leaves of Rhododendron catawbiense Michx

  • Hui Wei
  • Anik L. Dhanaraj
  • Lisa J. Rowland
  • Yan Fu
  • Stephen L. Krebs
  • Rajeev Arora
Original Article

DOI: 10.1007/s00425-004-1440-1

Cite this article as:
Wei, H., Dhanaraj, A.L., Rowland, L.J. et al. Planta (2005) 221: 406. doi:10.1007/s00425-004-1440-1

Abstract

An expressed sequence tag (EST) analysis approach was undertaken to identify major genes involved in cold acclimation of Rhododendron, a broad-leaf, woody evergreen species. Two cDNA libraries were constructed, one from winter-collected (cold-acclimated, CA; leaf freezing tolerance −53°C) leaves, and the other from summer-collected (non-acclimated, NA; leaf freezing tolerance −7°C) leaves of field-grown Rhododendron catawbiense plants. A total of 862 5′-end high-quality ESTs were generated by sequencing cDNA clones from the two libraries (423 from CA and 439 from NA library). Only about 6.3% of assembled unique transcripts were shared between the libraries, suggesting remarkable differences in gene expression between CA and NA leaves. Analysis of the relative frequency at which specific cDNAs were picked from each library indicated that four genes or gene families were highly abundant in the CA library including early light-induced proteins (ELIP), dehydrins/late embryogenesis abundant proteins (LEA), cytochrome P450, and beta-amylase. Similarly, seven genes or gene families were highly abundant in the NA library and included chlorophyll a/b-binding protein, NADH dehydrogenase subunit I, plastidic aldolase, and serine:glyoxylate aminotransferase, among others. Northern blot analyses for seven selected abundant genes confirmed their preferential expression in either CA or NA leaf tissues. Our results suggest that osmotic regulation, desiccation tolerance, photoinhibition tolerance, and photosynthesis adjustment are some of the key components of cold adaptation in Rhododendron.

Keywords

Cold hardinessEarly light-induced proteinExpressed sequence tagGenomicsLate embryogenesis abundant proteinRhododendron

Abbreviations

CA

Cold acclimated

ELIP

Early light-induced protein

EST

Expressed sequence tag

GAPDH

Glyceraldehyde-3-phosphate dehydrogenase

LEA

Late embryogenesis abundant protein

NA

Non-acclimated

Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • Hui Wei
    • 1
  • Anik L. Dhanaraj
    • 1
    • 2
  • Lisa J. Rowland
    • 2
  • Yan Fu
    • 3
  • Stephen L. Krebs
    • 4
  • Rajeev Arora
    • 1
  1. 1.Department of HorticultureIowa State UniversityAmesUSA
  2. 2.USDA-ARSFruit LabBeltsvilleUSA
  3. 3.Interdepartmental Genetics Graduate Program, Department of Genetics, and Developmental and Cellular BiologyIowa State UniversityAmesUSA
  4. 4.David G. Leach Research Station of the Holden ArboretumMentorUSA