Sex chromosome differentiation in Humulus japonicus Siebold & Zuccarini, 1846 (Cannabaceae) revealed by fluorescence in situ hybridization of subtelomeric repeat

By

Alexandrov, Oleg
Divashuk, Mikhail
Yakovin, Nickolay A.
Karlov, Gennady

Type

Article

Date of Publication

2012

Original Publication

Comparative cytogenetics : international journal of plant & animal cytogenetics, karyosystematics and molecular systematics

Volume

6

Series / Issue

Issue: 3

Pages

239-247

Subjects

fluorescence in situ hybridization , Humulus japonicus , sex chromosomes , sex determination in plants , subtelomeric repeat

Contributed by

Pensoft Publishers

Language

English

Published by

St. Petersburg, Russia [Published] with technical support of Zoological Institute RAS [2007]-

Identifiers

DOI: https://doi.org/10.3897/compcytogen.v6i3.3261

 

Abstract

Humulus japonicus Siebold & Zucc (Japanese hop) is a dioecious species of the family Cannabaceae. The chromosome number is 2n = 16 = 14 + XX for females and 2n = 17 = 14 + XY1Y2 for male. To date, no fluorescence in situ hybridization (FISH) markers have been established for the identification of H. japonicus sex chromosomes. In this paper, we report a method for the mitotic and meiotic sex chromosome differentiation in H. japonicus by FISH for HJSR, a high copy subtelomeric repeat. The signal is present in the subtelomeric region of one arm of the X chromosome. We demonstrate that males have two Y chromosomes that differ in FISH signal with the HJSR probe. Indeed, the HJSR probe hybridizes to a subtelomeric region on both arms of chromosome Y1 but not of chromosome Y2. The orientation and position of pseudoautosomal regions (PAR1 and PAR2) were also determined.