XML Feed for RxPG News   Add RxPG News Headlines to My Yahoo!   Javascript Syndication for RxPG News

Research Health World General
 
  Home
 
 Latest Research
 Cancer
 Psychiatry
 Genetics
  X Chromosome
  Genetic Disorders
   Brachydactyly
   Huntington's
   Fragile X Syndrome
   Progeria
   MSUD
  Cloning
 Surgery
 Aging
 Ophthalmology
 Gynaecology
 Neurosciences
 Pharmacology
 Cardiology
 Obstetrics
 Infectious Diseases
 Respiratory Medicine
 Pathology
 Endocrinology
 Immunology
 Nephrology
 Gastroenterology
 Biotechnology
 Radiology
 Dermatology
 Microbiology
 Haematology
 Dental
 ENT
 Environment
 Embryology
 Orthopedics
 Metabolism
 Anaethesia
 Paediatrics
 Public Health
 Urology
 Musculoskeletal
 Clinical Trials
 Physiology
 Biochemistry
 Cytology
 Traumatology
 Rheumatology
 
 Medical News
 Health
 Opinion
 Healthcare
 Professionals
 Launch
 Awards & Prizes
 
 Careers
 Medical
 Nursing
 Dental
 
 Special Topics
 Euthanasia
 Ethics
 Evolution
 Odd Medical News
 Feature
 
 World News
 Tsunami
 Epidemics
 Climate
 Business
Search

Last Updated: Aug 19th, 2006 - 22:18:38

Genetic Disorders Channel
subscribe to Genetic Disorders newsletter

Latest Research : Genetics : Genetic Disorders

   DISCUSS   |   EMAIL   |   PRINT
Exploring genetics of congenital malformations
Aug 19, 2006, 21:42, Reviewed by: Dr. Priya Saxena

"This is the first demonstration of a Tbx transcription factor to be localized outside the cell nucleus by a specific protein"

 
New research published in the August issue of the Journal of Cell Biology explains for the first time why congenital heart defects so often occur with limb deformities.

In their research into the molecular mechanisms that control embryonic limb and heart development, Northwestern University researcher Hans-Georg Simon and his laboratory group recently identified a new protein, LMP4, which binds and regulates activity of the Tbx4 and Tbx5 transcription factors. Tbx5 and Tbx4 proteins play a key role in limb and heart formation in virtually all vertebrates, from fish to birds to mice to humans.

Mutations in the respective Tbx5 and Tbx4 genes can cause severe birth defects characterized by upper limb and heart defects (Holt-Oram syndrome) or patella, hip and foot malformations (small patella syndrome), respectively, Simon explained.

"Despite the importance in embryogenesis and disease, the mechanisms by which the transcription factors encoded by these genes exert their functions are not well understood," Simon said.

In studies using chicken and zebrafish model systems, Simon and his lab members are trying to gain a complete picture of how the Tbx and LMP4 proteins interact in order to control the growth and particular shaping of the limbs and heart.

LMP4 apparently regulates Tbx protein activity in the cell by keeping the Tbx transcription factors bound to the actin cytoskeleton or releasing them to the nucleus. Actin is a contractile protein of muscle and is a major component of the cytoskeleton the "scaffolding" of the cell.

As the researchers wrote in their paper, this is the first demonstration of a Tbx transcription factor to be localized outside the cell nucleus by a specific protein. In addition, they demonstrate that removal of Tbx5 from the nucleus represses the transcription factor's ability to activate target genes in the limbs and heart.

"We are just beginning to understand the multitude of different cellular process that the Tbx proteins are involved in," concluded Simon. "The next step will be to identify the signals that regulate the dynamic interaction between LMP4 and Tbx5."
 

- August issue of the Journal of Cell Biology
 

www.northwestern.edu

 
Subscribe to Genetic Disorders Newsletter
E-mail Address:

 

Simon's collaborators on the study were Troy Camarata; Benjamin Bimber; Andre Kulisz; Teng-Leong Chew; and Jennifer Yeung, Children's Memorial Research Center and Northwestern University Feinberg School of Medicine. Simon is assistant professor of pediatrics at Northwestern University Feinberg School of Medicine and a cell and developmental biologist at Children's Memorial Research Center. Simon recently received a five-year, $1.7 million grant from the National Heart, Lung and Blood Institute to further elucidate the molecular basis of hand/heart birth defects associated with Tbx5 mutations.

Related Genetic Disorders News

Williams Syndrome, the brain and music
Exploring genetics of congenital malformations
FDA Approves Idursulfase As First Treatment for Hunter Syndrome
PARP1 inhibitors can protect Huntington's disease affected cells from damage
Gene therapy protects neurons in Huntington's disease
Huntingtin cleavage is caused by caspase-6
The risk of transmission of genetic disorders through donor's sperm
Liver transplants provide metabolic cure for maple syrup urine disease
Spinocerebellar ataxia type 5 (SCA5) gene pinpointed
Scientists probe connection between regulatory DNA and disease


For any corrections of factual information, to contact the editors or to send any medical news or health news press releases, use feedback form

Top of Page

 

© Copyright 2004 onwards by RxPG Medical Solutions Private Limited
Contact Us