The brown and white giant panda is a mutant with a unique coat color found only in the world. Qinling Mountains Chinese.
Kizai is the only brown panda living in captivity. Image credit: Ailie HM / CC BY-SA 4.0 Certificate.
“Variation in fur color has considerable adaptive and cultural value in mammals,” said study lead author Dengfeng Guan, Ph.D., from the Key Laboratory of Animal Ecology and Conservation Biology, Chinese Academy of Sciences, and colleagues.
“This property is directly determined by the ratio of eumelanin to pheomelanin and the density and distribution of melanosomes within the hair.”
“These factors are under complex control by hundreds of genes that influence different aspects of melanogenesis, including melanocyte proliferation and migration, melanin synthesis, and melanosome biogenesis and translocation.”
Giant panda (Airuropoda melanoruca) is one of the most charismatic flagship breeds, distinguished by its striking black and white coat.
However, the discovery brown panda (Ailuropoda melanoleuca qinlingensis) This photograph, taken in the Qinling Mountains of China's Shaanxi province, challenges the conventional wisdom that color photographs of pandas are never possible.
Recognized as a subspecies of the giant panda, this brown panda is extremely rare and is definitely designated as a national treasure.
Since the first brown panda was discovered in 1985, 11 records have been reported by official news or private communications, seven of which have been confirmed by photographs or physical objects. Three cases were from Buping County, two from Yang County, one from Taibai County, and one from Taibai County. Zhou Zhi.
All brown pandas are found only in the Qinling Mountains, indicating that they are endemic to this region.
“The first recorded brown panda, a female named Dan Dan, was rescued from Foping Nature Reserve to Xi'an Zoo in 1985,” the biologists explained.
“She then mated with the black panda Wang Wang and gave birth to a male black panda named Qing Qing in captivity.”
“Dan Dan passed away in 2000 and Chin Chin also died in 2006, leaving no descendants.”
“In 2009, Qi Zhai, a male brown panda cub, was rescued from Fo Ping Nature Reserve and is currently the only brown panda living in captivity.”
Dr. Guan and co-authors established two family trios related to the brown panda Qi Zai and sequenced their genomes.
They analyzed ecological and genetic data obtained from a long-term study of wild giant pandas in Fo Ping Nature Reserve.
Additionally, we investigated the cellular mechanisms underlying brown fur color based on microscopy and transmission electron microscopy analyses.
They are candidate mutations, viz. base 2 The gene is thought to be the most likely genetic basis for brown pandas.
They verified this deletion through sequencing an additional cohort of 192 black pandas and CRISPR-Cas9 knockout mice.
Their findings will not only provide insight into the genetic basis of coat color variation in brown pandas and wild animals, but will also guide the scientific breeding of rare brown pandas.
“The extremely small number of brown pandas and the nature of the frameshift deletion mutation suggest that this mutation may be a neutral or weakly deleterious mutation,” the authors said.
“Remarkably, the two brown pandas (Qi Zai and Dan Dan) are showing normal growth and reproduction; base 2 The knockout mice were viable, fertile, and had no obvious physical abnormalities, indicating that this mutation had no apparent negative impact on the physical fitness of these mice. ”
“However, other physiological effects of this mutation on brown pandas remain unclear. base 2 It is known to be involved in the Alzheimer's disease pathway. ”
“Given the small population size of Qinling giant pandas, weak deleterious mutations may be corrected by genetic drift effects.”
“Further studies on brown pandas and knockout mouse models will therefore provide valuable insight into the functional consequences of this mutation.”
“For a rare coat color mutant of the giant panda that has great scientific and ornamental value, our findings will provide guidance for the scientific breeding of brown pandas.”
of study Published online this week Proceedings of the National Academy of Sciences.
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Dengfeng Guan other. 2024. Color photography: homozygous 25 bp deletion base 2 Giant pandas can have brown and white coats. PNAS 121 (11): e2317430121; doi: 10.1073/pnas.2317430121
Source: www.sci.news
