Hostname: page-component-cd9895bd7-hc48f Total loading time: 0 Render date: 2024-12-23T09:04:27.097Z Has data issue: false hasContentIssue false

Comparative karyology, DNA methylation and restriction pattern analysis of male and female plants of the dioecious alga Chara tomentosa (Charophyceae)

Published online by Cambridge University Press:  18 May 2001

AGNIESZKA KUNACHOWICZ
Affiliation:
Department of Cytogenetics and Plant Molecular Biology, University of Lódz, Banacha 12/16, 90–237 Lódz, Poland
PIOTR LUCHNIAK
Affiliation:
Department of Cytogenetics and Plant Molecular Biology, University of Lódz, Banacha 12/16, 90–237 Lódz, Poland
MARIA J. OLSZEWSKA
Affiliation:
Department of Cytogenetics and Plant Molecular Biology, University of Lódz, Banacha 12/16, 90–237 Lódz, Poland
TOMASZ SAKOWICZ
Affiliation:
Department of Cytogenetics and Plant Molecular Biology, University of Lódz, Banacha 12/16, 90–237 Lódz, Poland
Get access

Abstract

Comparison of karyology, restriction patterns and DNA methylation levels (as gender separation could be related to some epigenetic mechanism, e.g. DNA methylation) has been performed between male and female individuals of the dioecious species, Chara tomentosa. In contrast to angiosperms, sex determination systems in Charophyceae have not been studied. High-performance liquid chromatography (HPLC) showed that the cytosine methylation level in female plants of Chara tomentosa reached 5·9 %, while in male plants it reached 9·1 %. Karyological analysis did not show any differences in metaphase chromosome number or morphology between sexes. Cytophotometric measurements of DNA content revealed differences in 1C DNA content: 7·0 pg in females and 7·4 pg in males (p < 0·001). Computer image analysis showed that in the interphase nuclei condensed chromatin consists of 34·3 % of the total chromatin in female plants, while in males it was 29·6 % of total chromatin (p < 0·001). Digestion of isolated DNAs with 12 enzymes showed poor enzymatic cleavage (for example with SacI) or restriction patterns which differed between the sexes (TaqI, Bst0I). The restriction endonucleases RsaI and BamHI revealed repetitive DNA families in males. BamHI generated bands of over 3000 bp while RsaI revealed populations of fragments 650–2000 bp long. DNA isolated from male individuals of C. tomentosa was less susceptible than DNA isolated from female plants to digestion with enzymes that are inhibited by methylation of dC residues (HpaII, HhaI).

Type
Research Article
Copyright
© 2001 British Phycological Society

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)