Welcome to The Visible Embryo

Home- - -History-- -Bibliography- -Pregnancy Timeline- --Prescription Drugs in Pregnancy- -- Pregnancy Calculator- --Female Reproductive System- News Alerts -Contact

Welcome to The Visible Embryo, a comprehensive educational resource on human development from conception to birth.

The Visible Embryo provides visual references for changes in fetal development throughout pregnancy and can be navigated via fetal development or maternal changes.

The National Institutes of Child Health and Human Development awarded Phase I and Phase II Small Business Innovative Research Grants to develop The Visible Embryo. Initally designed to evaluate the internet as a teaching tool for first year medical students, The Visible Embryo is linked to over 600 educational institutions and is viewed by more than ' million visitors each month.


WHO International Clinical Trials Registry Platform
The World Health Organization (WHO) has created a new Web site to help researchers, doctors and patients obtain reliable information on high-quality clinical trials. Now you can go to one website and search all registers to identify clinical trial research underway around the world!



Home

History

Bibliography

Pregnancy Timeline

Prescription Drug Effects on Pregnancy

Pregnancy Calculator

Female Reproductive System

Contact The Visible Embryo

News Alerts Archive

Disclaimer: The Visible Embryo web site is provided for your general information only. The information contained on this site should not be treated as a substitute for medical, legal or other professional advice. Neither is The Visible Embryo responsible or liable for the contents of any websites of third parties which are listed on this site.
Content protected under a Creative Commons License.

No dirivative works may be made or used for commercial purposes.

Return To Top Of Page
Pregnancy Timeline by SemestersFemale Reproductive SystemFertilizationThe Appearance of SomitesFirst TrimesterSecond TrimesterThird TrimesterFetal liver is producing blood cellsHead may position into pelvisBrain convolutions beginFull TermWhite fat begins to be madeWhite fat begins to be madeHead may position into pelvisImmune system beginningImmune system beginningPeriod of rapid brain growthBrain convolutions beginLungs begin to produce surfactantSensory brain waves begin to activateSensory brain waves begin to activateInner Ear Bones HardenBone marrow starts making blood cellsBone marrow starts making blood cellsBrown fat surrounds lymphatic systemFetal sexual organs visibleFinger and toe prints appearFinger and toe prints appearHeartbeat can be detectedHeartbeat can be detectedBasic Brain Structure in PlaceThe Appearance of SomitesFirst Detectable Brain WavesA Four Chambered HeartBeginning Cerebral HemispheresEnd of Embryonic PeriodEnd of Embryonic PeriodFirst Thin Layer of Skin AppearsThird TrimesterDevelopmental Timeline
Click weeks 0 - 40 and follow fetal growth
Google Search artcles published since 2007
 
Home--History--Bibliography- -Pregnancy Timeline- Prescription Drugs/Pregnancy- Pregnancy Calculator - Reproductive System- -News Alerts

February 6, 2012--------News Archive Return to: News Alerts

Left: Head; Right: Tail
Ancestors of a fruit fly's gut and heart muscles.
Credit: EMBL/Furlong

WHO Child Growth Charts

What Is Your BMI?

       

Gene Switches Hold Clues to "Family Tree"

If you wanted to draw your family tree, you could start by searching for people who share your gene switches.

Cells don’t have surnames, but scientists at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, have found that genetic switches called enhancers, and the molecules activating those switches – transcription factors – can be used as clues to a cell’s developmental history.

The study, published in Cell, also unveils a new model for how enhancers function.

Guillaume Junion and Mikhail Spivakov, collaborated to look at fruit fly embryos' heart muscle cells, finding active enhancers aren’t the only ones that have groups of transcription factors attached.

Surprisingly, enhancers that should be active only in the neighbouring gut muscle are also occupied by transcription factors in heart cells.

“Although it may seem counter-intuitive to leave unnecessary genetic switches available for activation and then have to actively suppress them, the findings make sense in developmental terms,” says Furlong.

Both heart and gut muscle cells develop from the same pool of precursor cells. Enhancers for both groups seem to be made available to transcription factors in the precursor cells, before they ‘grow up’ to be either heart or muscle cells.

If this is the case, scientists could work out the relationships between cells by looking at what occupied enhancers they share.

Intriguingly, heart muscle cells don’t actually have the transcription factors that bind to gut enhancers in gut muscle cells. Instead, the gut enhancers in heart cells were occupied by transcription factors produced only by the heart.

Furlong and colleagues found that transcription factors are able to attach themselves to enhancers in groups, others bind directly to the enhancer’s DNA and some bind to enhancer-bound transcription factors.

This means that the genetic sequence of these enhancers can vary greatly, even though they function as a united group – a strategy that differs from the two ways in which enhancers were already known to function.

This flexibility in the enhancer’s genetic sequence means that it can mutate without disastrous effects, adding to the fruit fly's evolutionary flexibility.

The EMBL scientists are now investigating how far that flexibility goes.

They are looking at variation in another species of fruit fly, Drosophila virilis, which is genetically as different from the commonly-used Drosophila melanogaster as humans are from chickens.

Junion, G., Spivakov, M., Girardot, C., Braun, M., Gustafson, E.H., Birney, E. & Furlong, E.E.M. A transcription factor collective defines cardiac cell fate and reflects the developmental history of this cell lineage. Cell, 3 February 2012. DOI:10.1016/j.cell.2012.01.030.

Original article: http://www.embl.de/aboutus/communication_outreach/
media_relations/2012/120202_Heidelberg/index.html