HOME >> BIOLOGY >> NEWS
Counting X Chromosomes To Determine Sex

November 12, 1998—In mammals, the developmental decision for a fetus to become male or remain female rests with the Y chromosome—if the Y chromosome is present, the fetus becomes male. But many species lack a Y chromosome, so the choice must be made by counting X chromosomes instead, which is not an easy task.

Barbara Meyer, a Howard Hughes Medical Institute investigator, and her colleagues at the University of California, Berkeley, have discovered a signal, which they call SEX-1, that helps the nematode worm C. elegans tally its X chromosomes. SEX-1, a hormone receptor found in the cell nucleus, belongs to a family of proteins widely used by animals to translate environmental cues into decisions on how to regulate gene expression. A similar molecule may be involved in the first steps of mammalian sex determination.

"The process of sex determination may differ from organism to organism, but the underlying mechanisms may be much more similar," says Meyer. She and her colleagues report their findings in the November 12, 1998 issue of the journal Nature. The work was partly supported by grants from the National Institutes of Health.

Among C. elegans, worms with two X chromosomes, or XX animals, usually develop as hermaphrodites, while those with a single X chromosome, known as XO animals, develop as males. Hermaphrodites, given a choice, will mate with males, but unlike females of other species, hermaphrodites produce sperm that they can use to fertilize their own eggs in the absence of males.

The X chromosome in C. elegans, says Meyer, "has at least four genes, probably five or six," that signal the chromosome's presence All those X signals are believed to dampen the activity of a pivotal protein, called XOL-1, that processes the incoming X signals and steers organisms' sexual fates. When the X signals are abundant enough to overwh
'"/>

Contact: Jim Keeley
keeleyj@hhmi.org
301-215-8858
Howard Hughes Medical Institute
12-Nov-1998


Page: 1 2 3

Related biology news :

1. Counting foxes before the last tally-ho
2. Counting the molecules that pull cells apart
3. Counting the molecules that pull cells apart
4. Counting semi-viable bacteria in cheese
5. Counting salmon essential measure of recovery efforts
6. Counting the cost of genome projects
7. Counting elephants by monitoring sounds
8. Detecting Deer: New Method For Counting Population In Urban Areas
9. Chromosomes are nibbled before they fuse, researchers report
10. Discovery: Chromosomes Found To End In Big Loops
11. COGA Genome Scan Suggests Linkage On Chromosomes 1,2,4, And 7

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:11/14/2019)... ... November 13, 2019 , ... ... Robert Peterson, RAC , a regulatory affairs and program management executive with more ... medical device industries, has joined the firm as an Expert Consultant. , ...
(Date:11/12/2019)... ... November 12, 2019 , ... ... proposals from nonprofit U.S. universities and research institutions for its Instrumentation Grant ... of up to $1.2 million per site for the acquisition of instrumentation, development ...
(Date:11/7/2019)... ... November 07, 2019 , ... R3 Stem Cell is now offering ... rest of 2019. The code to use during checkout is FIFTYOFF and applies to ... the nation’s leader in regenerative therapies with over 12,000 successful stem cell procedures performed ...
Breaking Biology News(10 mins):
(Date:11/5/2019)... ... 05, 2019 , ... Focal Healthcare , an innovator ... Fusion Bx 2.0 prostate fusion biopsy solution. By combining information from multiparametric MRI ... give urologists across Europe the ability to perform targeted transrectal and transperineal prostate ...
(Date:11/2/2019)... ... October 31, 2019 , ... ... pharma artificial intelligence pioneer tellic. drug360 brings tellic’s expertise in biomedical language ... allows researchers to quickly uncover relationships between genes, diseases, variants, phenotypes, and other ...
(Date:10/29/2019)... ... October 29, 2019 , ... ... its Silver sponsorship and cold chain validation workshop at the Biomanufacturing World Summit ... San Diego, California. , The Biomanufacturing World Summit brings together pharmaceutical ...
(Date:10/22/2019)... ... ... Catalent, a global leader in clinical supply services, today announced that Ann ... a panel session titled “Cell and Gene Therapy Logistics” at the upcoming Health and ... Oct. 28-30, 2019. , The panel session, on Wednesday, Oct. 30 at 8:30 a.m., ...
Breaking Biology Technology:
Cached News: