Choh Hao Li
Encyclopedia
Choh Hao Li ' onMouseout='HidePop("12334")' href="/topics/Pinyin">pinyin
: Lǐ Zhuōhào) (April 21 1913—November 28, 1987) was a Chinese-born U.S. biochemist who discovered, in 1966, that human pituitary growth hormone
(somatotropin) consists of a chain of 256 amino acids. In 1970 he succeeded in synthesizing this hormone, the largest protein molecule
synthesized
up to that time.
Li was born in Guangzhou
and educated at the Nanjing University
. In 1935 he emigrated to the USA, where he took up postgraduate studies at the University of California
at Berkeley
and later joined the staff. He became professor in 1950. In 1955 he was elected as Academician of Academia Sinica
, Republic of China.
Li spent his entire academic career studying the pituitary-gland hormones. In collaboration with various co-workers, he isolated several protein hormones, including adrenocorticotropic hormone
(ACTH), which stimulates the adrenal cortex
to increase its secretion of corticoids. In 1956, Li and his group showed that ACTH consists of 39 amino acids arranged in a specific order, and that the whole chain of the natural hormone is not necessary for its action. He isolated another pituitary hormone called melanocyte-stimulating hormone
(MSH) and found that not only does this hormone produce some effects similar to those produced by ACTH, but also that part of the amino acid chain of MSH is the same as that of ACTH.
Pinyin
Pinyin is the official system to transcribe Chinese characters into the Roman alphabet in China, Malaysia, Singapore and Taiwan. It is also often used to teach Mandarin Chinese and spell Chinese names in foreign publications and used as an input method to enter Chinese characters into...
: Lǐ Zhuōhào) (April 21 1913—November 28, 1987) was a Chinese-born U.S. biochemist who discovered, in 1966, that human pituitary growth hormone
Hormone
A hormone is a chemical released by a cell or a gland in one part of the body that sends out messages that affect cells in other parts of the organism. Only a small amount of hormone is required to alter cell metabolism. In essence, it is a chemical messenger that transports a signal from one...
(somatotropin) consists of a chain of 256 amino acids. In 1970 he succeeded in synthesizing this hormone, the largest protein molecule
Molecule
A molecule is an electrically neutral group of at least two atoms held together by covalent chemical bonds. Molecules are distinguished from ions by their electrical charge...
synthesized
Chemical synthesis
In chemistry, chemical synthesis is purposeful execution of chemical reactions to get a product, or several products. This happens by physical and chemical manipulations usually involving one or more reactions...
up to that time.
Li was born in Guangzhou
Guangzhou
Guangzhou , known historically as Canton or Kwangchow, is the capital and largest city of the Guangdong province in the People's Republic of China. Located in southern China on the Pearl River, about north-northwest of Hong Kong, Guangzhou is a key national transportation hub and trading port...
and educated at the Nanjing University
Nanjing University
Nanjing University , or Nanking University, is one of the oldest and most prestigious institutions of higher learning in China...
. In 1935 he emigrated to the USA, where he took up postgraduate studies at the University of California
University of California
The University of California is a public university system in the U.S. state of California. Under the California Master Plan for Higher Education, the University of California is a part of the state's three-tier public higher education system, which also includes the California State University...
at Berkeley
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...
and later joined the staff. He became professor in 1950. In 1955 he was elected as Academician of Academia Sinica
Academia Sinica
The Academia Sinica , headquartered in the Nangang District of Taipei, is the national academy of Taiwan. It supports research activities in a wide variety of disciplines, ranging from mathematical and physical sciences, to life sciences, and to humanities and social sciences.Academia Sinica has...
, Republic of China.
Li spent his entire academic career studying the pituitary-gland hormones. In collaboration with various co-workers, he isolated several protein hormones, including adrenocorticotropic hormone
Adrenocorticotropic hormone
Adrenocorticotropic hormone , also known as 'corticotropin', 'Adrenocorticotrophic hormone', is a polypeptide tropic hormone produced and secreted by the anterior pituitary gland. It is an important component of the hypothalamic-pituitary-adrenal axis and is often produced in response to biological...
(ACTH), which stimulates the adrenal cortex
Adrenal cortex
Situated along the perimeter of the adrenal gland, the adrenal cortex mediates the stress response through the production of mineralocorticoids and glucocorticoids, including aldosterone and cortisol respectively. It is also a secondary site of androgen synthesis.-Layers:Notably, the reticularis in...
to increase its secretion of corticoids. In 1956, Li and his group showed that ACTH consists of 39 amino acids arranged in a specific order, and that the whole chain of the natural hormone is not necessary for its action. He isolated another pituitary hormone called melanocyte-stimulating hormone
Melanocyte-stimulating hormone
The melanocyte-stimulating hormones are a class of peptide hormones that are produced by cells in the intermediate lobe of the pituitary gland...
(MSH) and found that not only does this hormone produce some effects similar to those produced by ACTH, but also that part of the amino acid chain of MSH is the same as that of ACTH.
External links
- Choh Hao Li Papers – University of California, San Francisco Library, Archives and Special Collections
- Biography and chronology
- History of UCSF biography
- Short biography