(Press-News.org) Coast redwoods are famous for being the tallest trees in the world, but their height is not the only thing that sets them apart. Unlike most conifer trees, coast redwoods can reproduce by sprouting from cut stumps, fallen logs, and roots. Researchers from the University of California, Berkeley, are uncovering important information about patterns of coast redwood clones with a new DNA analysis method that could help forest management and preservation efforts.
The new method, described in a recent issue of Applications of Plant Sciences, will enable scientists to identify clonal lineages and study how clonal diversity varies throughout the geographic range of this species. Coast redwoods are among the oldest living trees on earth and, although they once occupied much of the northern hemisphere, today's native coast redwood forests can only be found in a 450-mile strip of land along the coast of northern California to southern Oregon.
To date, very little research has been done to elucidate the clonal patterns of coast redwood. This is partly due to another aspect that sets redwoods apart from other woody plants--they are hexaploid, meaning that there are six copies of each homologous chromosome in the genome, instead of two.
"Genetic analyses of polyploid organisms are difficult due to higher numbers of alleles," explains Lakshmi Narayan, the graduate student who led the UC Berkeley study. "In addition to their hexaploid condition, another challenge in determining the genotypic identity of clonal plants is the possibility of somatic mutation, where a mutation occurs that changes the genotype of an individual in a clonal lineage. These mutations have the potential to confound genotyping studies seeking to identify the origin of shoots."
Narayan designed the new protocol to overcome challenges associated with mutations and with the high genetic copy number in redwood DNA. Narayan and her colleagues tested the clonal identification protocol by collecting DNA samples from 770 redwoods and successfully identified 449 distinct clones.
A key aspect of the new method is the use of short repeating DNA sequences from different coast redwood tissue types. The short DNA sequences, known as microsatellites, are present in all living organisms and widely used to distinguish individuals from one another. The researchers analyzed microsatellite data from coast redwood cambium, leaf, and sprout tissue.
"One novel aspect of our protocol was the use of different tissue types to verify consistent identification of alleles between samples," explains Narayan. "Requiring that alleles amplified in multiple tissue types from the same individual before scoring them made our protocol more conservative. This potentially reduced potential for misidentification. The other novel aspect of our work was the extensive use of data simulation to test the resolution of our genetic markers and scoring protocol."
Because they are a fast-growing tree species, young redwoods are commercially valued for timber production while ancient redwoods remain protected. Genetic data produced from the new protocol could help guide sustainable forest management of commercial young-growth forests and also improve efforts to preserve ancient redwood populations.
Says Narayan, "We hope the methods presented in this paper will be applicable to other species, in addition to being useful for genotyping coast redwoods. Our future research will employ this methodology to study the variation in levels of clonal diversity throughout the species' range, and look at how clonal reproduction may affect the physical structure of redwood forests."
INFORMATION:
Lakshmi Narayan, Richard S. Dodd, and Kevin L. O'Hara. 2015. A genotyping protocol for multiple tissue types from the polyploid tree species Sequoia sempervirens (Cupressaceae). Applications in Plant Sciences 3(3): 1400110. doi:10.3732/apps.1400110
Applications in Plant Sciences (APPS) is a monthly, peer-reviewed, open access journal focusing on new tools, technologies, and protocols in all areas of the plant sciences. It is published by the Botanical Society of America, a nonprofit membership society with a mission to promote botany, the field of basic science dealing with the study and inquiry into the form, function, development, diversity, reproduction, evolution, and uses of plants and their interactions within the biosphere. APPS is available as part of BioOne's Open Access collection.
For further information, please contact the APPS staff at apps@botany.org.
Northridge, CA (March 30, 2015) - A recent analysis published in the Journal of Human Nutrition & Food Science reveals a beneficial relationship between dietary magnesium intake and diabetes-related outcomes including decreased risk for metabolic syndrome, obesity or overweight, elevated blood pressure, and reduced HDL (good) cholesterol(1).
This secondary analysis examined the relationship between dietary magnesium intake from food and food combined with supplements and diabetes and other related health factors in adults (? 20 years) using data from the National Health ...
RENO, Nev. - New research into the changing ecology of thousands of shallow lakes on the North Slope of Alaska suggests that in scenarios of increasing global temperatures, methane-generating microbes, found in thawing lake sediments, may ramp up production of the potent greenhouse gas - which has a global warming potential 25 times greater than carbon dioxide.
A study published this month in Geobiology - resulting from five-years of collaborative research led by Nevada's Desert Research Institute (DRI) and including scientists from NASA's Jet Propulsion Laboratory (JPL), ...
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Modern medicine relies on the widespread availability of effective antimicrobials ...
New research from the University of Copenhagen has found that the beneficial effects of exercise are more important for our health than the negative effects of air pollution, in relation to the risk of premature mortality. In other words, benefits of exercise outweigh the harmful effects of air pollution.
The study shows that despite the adverse effects of air pollution on health, air pollution should be not perceived as a barrier to exercise in urban areas. "Even for those living in the most polluted areas of Copenhagen, it is healthier to go for a run, a walk or to ...
PULLMAN, Wash. -- Washington State University researchers have found that an unexpectedly high percentage of young people experience "exploding head syndrome," a psychological phenomenon in which they are awakened by abrupt loud noises, even the sensation of an explosion in their head.
Brian Sharpless, a Washington State University assistant professor and director of the university psychology clinic, found that nearly one in five -- 18 percent -- of college students interviewed said they had experienced it at least once. It was so bad for some that it significantly impacted ...
1. USPSTF reviews evidence to update recommendations on iron supplementation and deficiency screening in pregnant women
The U.S. Preventive Services Task Force (USPSTF) reviewed published evidence to update its recommendations on iron supplementation and screening for iron deficiency anemia in pregnant women. The evidence review is being published in Annals of Internal Medicine simultaneously with an evidence review in Pediatrics on screening for iron deficiency anemia in young children.
Iron needs increase during pregnancy due to the demands of the growing fetus and ...
Distasteful though it sounds, the transplantation of fecal matter is more successful for treating Clostridium difficile infections than previously thought.
The research, published in the open access journal Microbiome, reveals that healthy changes to a patient's microbiome are sustained for up to 21 weeks after transplant, and has implications for the regulation of the treatment.
Clostridium difficile infections are a growing problem, leading to recurrent cases of diarrhea and severe abdominal pain, with thousands of fatalities worldwide every year. The infection is ...
Recreational users of coastal waters such as swimmers and surfers are at risk of exposure to antibiotic resistant bacteria, according to new research published this week.
In the first study of its kind, scientists at the University of Exeter Medical School have assessed the amount of water ingested during different water sports and combined this with water sampling data to estimate people's exposure to bacteria resistant to antibiotics.
Using data gathered across England and Wales in 2012, they estimated that over 6.3 million water sport sessions resulted in one type ...
Parents of obese children may not be able to recognise that their child is overweight unless they are at very extreme levels of obesity, according to research led by London School of Hygiene & Tropical Medicine and UCL Institute of Child Health, research partner of Great Ormond Street Hospital.
The work, which is published in the British Journal of General Practice, finds that parents are additionally more likely to underestimate their child's weight if they are Black or south Asian (v white), from more deprived backgrounds or if their offspring is male. The identification ...
March 29, 2015 - San Francisco - Even rats can imagine: A new study finds that rats have the ability to link cause and effect such that they can expect, or imagine, something happening even if it isn't. The findings are important to understanding human reasoning, especially in older adults, as aging degrades the ability to maintain information about unobserved events.
"What sets humans apart from the rest of the animal kingdom is our prodigious ability to reason. But what about human reasoning is truly a human-unique feature and what aspects are shared with our nonhuman ...
