Navigation Links
Nailing down a crucial plant signaling system

Stanford, CA Plant biologists have discovered the last major element of the series of chemical signals that one class of plant hormones, called brassinosteroids, send from a protein on the surface of a plant cell to the cell's nucleus. Although many steps of the pathway were already known, new research from a team including Carnegie's Ying Sun and Zhiyong Wang fills in a missing gap about the mechanism through which brassinosteroids cause plant genes to be expressed. Their research, which will be published online by Nature Cell Biology on January 23, has implications for agricultural science and, potentially, evolutionary research.

"Brassinosteroids are found throughout the plant kingdom and regulate many aspects of growth and development, as well as resistance from external stresses," said Wang. "Mutant plants that are deficient in brassinosteroids show defects at many phases of the plant life cycle, including reduced seed germination, irregular growth in the absence of light, dwarfism, and sterility."

Previous research had identified a pathway of chemical signals that starts when a brassinosteroid binds to a receptor on the surface of a plant cell and activates a cascade of activity that consists of adding and removing phosphates from a series of proteins.

When brassinosteroids are not present, a protein in this pathway called BIN2 acts to add phosphates to two other proteins called BZR1 and BZR2, which are part of a special class of proteins called transcription factors. The phosphates inhibit the transcription factors. But when a brassinosteroid binds to the cell-surface receptor, BIN2 is deactivated, and as a result phosphates are removed from the two transcription factors. As a result, BZR1 and BZR2 can enter the cell's nucleus, where they bind directly to DNA molecules and promote a wide variety of gene activity.

Before this new research, the protein that detaches the phosphates and allows BZR1 and BZR2 to work was unknown. Using an extensive array of research techniques, the team was able to prove that a protein called protein phosphatase 2A (PP2A) is responsible.

"We discovered that PP2A is a key component of the brassinosteroid signaling pathway," Wang said. "This discovery completes the core signaling module that relays extracellular brassinosteroids to cue activity in the nucleus."

Further research is needed to determine whether brassinosteroid binding activates PP2A, or just deactivates BIN2, thus allowing PP2A to do this job. Additionally, PP2A is involved in a plant's response to gravity and light, among other things.

This aspect of the brassinosteroid signaling pathway bears some surprising resemblances to signaling pathways found in many members of the animal kingdom. More research could demonstrate details of the evolutionary split between non-protozoan animals and plants.


Contact: Zhiyong Wang
Carnegie Institution

Related biology news :

1. Hidden infections crucial to understanding, controlling disease outbreaks
2. Mayo researchers identify dangerous two-faced protein crucial to breast cancer spread and growth
3. In lung cancer, silencing one crucial gene disrupts normal functioning of genome
4. Simplicity is crucial to design optimization at nanoscale
5. Caffeic acid inhibits colitis in a mouse model -- is a drug-metabolizing gene crucial?
6. For HIV-infected children, quality of caregiver relationship is crucial
7. Crucial differences found among Latino populations facing heart disease risks
8. Vitamin D crucial to activating immune defenses
9. Payment Default Risks Remain a Crucial Issue for Businesses Across Europe
10. Formula discovered for longer plant life
11. Commercial aquatic plants offer cost-effective method for treating wastewater
Post Your Comments:
(Date:10/23/2015)... GOLETA, California , October 23, 2015 ... and SensoMotoric Instruments (SMI) announce a mobile plug and ... captured during interactive real-world tasks SensoMotoric Instruments ... of their established wearable solutions for eye tracking and ... behavior captured with SMI Eye Tracking Glasses 2w ...
(Date:10/22/2015)... (NASDAQ: SYNA ), a leading developer of human interface solutions, ... 2015. --> --> Net ... over the comparable quarter last year to $470.0 million. Net income ... $0.62 per diluted share. --> ... 2016 grew 39 percent over the prior year period to $56.9 ...
(Date:10/22/2015)... , October 22, 2015 ... "Company"), a biometric authentication company focused on the growing ... wallet announces a one year collaboration with well-known celebrity ... ) ,      (Photo: ... member of NSYNC from 1995 to 2002, Joey was ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... RALEIGH, N.C. , Nov. 24, 2015  Clintrax Global, Inc., ... Raleigh, North Carolina , today announced that the company has ... earnings represented a 391% quarter on quarter growth posted for Q3 ... Kingdom and Mexico , with the ... place in December 2015. --> United Kingdom ...
(Date:11/24/2015)... ... November 24, 2015 , ... This fall, global software ... events in five states to develop and pitch their BIG ideas to improve health ... state are competing for votes to win the title of SAP's Teen Innovator, an ...
(Date:11/24/2015)... , November 24, 2015 SHPG ) announced ... in the Piper Jaffray 27 th Annual Healthcare Conference in ... 1, 2015, at 8:30 a.m. EST (1:30 p.m. GMT). --> ... Financial Officer, will participate in the Piper Jaffray 27 th ... NY on Tuesday, December 1, 2015, at 8:30 a.m. EST (1:30 ...
(Date:11/24/2015)... , Nov. 24, 2015  Tikcro Technologies Ltd. (OTCQB: TIKRF) today announced ... 29, 2015 at 11:00 a.m. Israel time, at ... 98 Yigal Allon Street, 36 th Floor, Tel Aviv, ... Eric Paneth and Izhak Tamir to the Board of ... as external directors; , approval of an amendment to certain terms ...
Breaking Biology Technology: