Featured Research

from universities, journals, and other organizations

Kiwifruit: Curious Chromosomes Of A Curious Fruit

Date:
March 15, 2009
Source:
BioMed Central
Summary:
Incipient sex chromosomes have been found in New Zealand's eponymous export, the kiwifruit. Researchers have mapped the kiwifruit genome and pin-pointed the sex-determining locus.

Kiwifruit. Incipient sex chromosomes have been found in New Zealand's eponymous export, the kiwifruit. Researchers have mapped the kiwifruit genome and pin-pointed the sex-determining locus.
Credit: iStockphoto/Vladimir Vladimirov

Incipient sex chromosomes have been found in New Zealand's eponymous export, the kiwifruit. Researchers have mapped the kiwifruit genome and pin-pointed the sex-determining locus.

It has previously been suggested that, among the kiwifruit plant's small (<1um) chromosomes, lie a pair of X/Y-like chromosomes that result in its dioecism. Now a team led by Lena Fraser and colleagues at the New Zealand Institute for Plant and Food Research has confirmed this suggestion by mapping the genome of the golden kiwifruit. The genome has been mapped with 644 microsatellite markers from three genetic libraries (two from the New Zealand Institute for Plant and Food Research and one from the University of Udine, Italy). These showed 29 linkage groups, represented expression of 587 genes, and revealed that sex-linked sequence characterised amplified region (SCAR) markers and the flower sex phenotype were mapping to a subtelomeric region that bears the hallmarks of an early sex-determining locus.

The mapping of this sex-determining locus to a subtelomeric region fits with previous published work on chromosome pairing and also the authors own observations. Whilst studying kiwifruit karyotypes, the research team observed that in the pollen mother cells undergoing meiosis one of the 29 pairs of chromosomes did not pair tightly in a region close to one end. An absence of pairing means that the male-specific region on the Y is inherited as a unit, maintaining sexual dimorphism. Based on the genetic structure they have now defined for this non-recombining sex-determining region, the authors suggest that at least two linked genes on the putative Y chromosome are responsible for dioecy: one suppressing pistil formation and one for pollen development.

Of more than 60 species of Actinidia (kiwifruit), only two have been widely cultivated so far, and there is potential for breeding new varieties. All Actinida species are dioecious, and the authors say they are likely to have similar sex-determining regions. The authors work in producing female, male and consensus genetic linkage maps for the golden kiwifruit, A. chinensis and identifying the sex-determining region may provide the key to fully exploiting this relatively recent cultivar.

According to Fraser, 'The gene-rich map we have constructed will be a valuable resource for quantitative trait loci analyses to identify markers related to traits of importance in breeding new and novel kiwifruit for the markets of the world.'


Story Source:

The above story is based on materials provided by BioMed Central. Note: Materials may be edited for content and length.


Journal Reference:

  1. Lena G Fraser, Gianna K Tsang, Paul M Datson, H NIHAL De Silva, Catherine F Harvey, Geoffrey P Gill, Ross N Crowhurst and Mark A McNeilage. A gene-rich linkage map in the dioecious species Actinidia chinensis (kiwifruit) reveals putative X/Y sex-determining chromosomes. BMC Genomics, (in press)

Cite This Page:

BioMed Central. "Kiwifruit: Curious Chromosomes Of A Curious Fruit." ScienceDaily. ScienceDaily, 15 March 2009. <www.sciencedaily.com/releases/2009/03/090309205325.htm>.
BioMed Central. (2009, March 15). Kiwifruit: Curious Chromosomes Of A Curious Fruit. ScienceDaily. Retrieved September 30, 2014 from www.sciencedaily.com/releases/2009/03/090309205325.htm
BioMed Central. "Kiwifruit: Curious Chromosomes Of A Curious Fruit." ScienceDaily. www.sciencedaily.com/releases/2009/03/090309205325.htm (accessed September 30, 2014).

Share This



More Plants & Animals News

Tuesday, September 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

California University Designs Sustainable Winery

California University Designs Sustainable Winery

Reuters - US Online Video (Sep. 27, 2014) Amid California's worst drought in decades, scientists at UC Davis design a sustainable winery that includes a water recycling system. Vanessa Johnston reports. Video provided by Reuters
Powered by NewsLook.com
Argentina Worries Over Decline of Soybean Prices

Argentina Worries Over Decline of Soybean Prices

AFP (Sep. 27, 2014) The drop in price of soy on the international market is a cause for concern in Argentina, as soybean exports are a major source of income for Latin America's third largest economy. Duration: 01:10 Video provided by AFP
Powered by NewsLook.com
Mama Bear, Cubs Hang out in California Backyard

Mama Bear, Cubs Hang out in California Backyard

Reuters - US Online Video (Sep. 27, 2014) A mama bear and her two cubs climb trees, wrestle and take naps in the backyard of a Monrovia, California home. Vanessa Johnston reports. Video provided by Reuters
Powered by NewsLook.com
'Crazy' Climate Forces Colombian Farmers to Adapt

'Crazy' Climate Forces Colombian Farmers to Adapt

AFP (Sep. 26, 2014) Once upon a time, farming was a blissfully low-tech business on Colombia's northern plains. Duration: 02:05 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins