Skip to main content

The flower clock: How a small protein helps flowers to develop right and on time

The flower clock: How a small protein helps flowers to develop right and on time

How flowers form properly within a limited time frame has been a mystery, at least until now. Researchers from Japan and China have discovered how a multi-tasking protein helps flowers to develop as expected.

In a study published in Proceedings of the National Academy of Sciences U.S.A., researchers from Nanjing University and Nara Institute of Science and Technology have revealed that a small protein plays multiple roles to ensure that floral reproductive organs are formed properly within a short space of time.

Flowers develop from floral meristems, which differentiate to produce the sepals, petals, stamens, and carpels. The proper development of these floral organs depends on meristem development being completed within a certain time period. In the early stages of flower development, stem cells provide the cell source for floral organ formation. In floral meristems, stem cell activities are maintained via a feedback loop between WUSCHEL (WUS), a gene that identifies floral stem cells, and CLAVATA3 (CLV3), a stem cell marker gene that is activated and sustained by WUS.

“A small protein called KNUCKLES (KNU) represses WUS directly, which leads to the completion of floral stem cell activity at the right time,” says lead author Erlei Shang of the study. “What isn’t fully understood is how the robust floral stem cell activity finishes within a limited time period to ensure carpel development.”

“The team’s research revealed that in Arabidopsis thaliana, KNU can completely deactivate the robust floral meristems at a particular floral stage, thanks to the multiple functions that KNU carries out via its position-specific roles,” says senior author Toshiro Ito.

KNU both represses and silences WUS, and directly represses CLV3 and CLV1 (a gene that encodes a receptor for the CLV3 peptide). Consequently, KNU eliminates the CLV3-WUS feedback loop via transcriptional and epigenetic mechanisms (i.e., those that do not involve changes in the underlying DNA sequences). Additionally, KNU interacts physically with the WUS protein, which inhibits WUS from sustaining CLV3, disrupting interactions that are required for the maintenance of floral meristems.

“Our results reveal a regulatory pathway where KNU plays a key role in supporting the completion of floral meristem development within a short time window, and ensures that flower reproductive organs are properly formed,” says corresponding author Bo Sun.

The results of this research will be useful for genetic studies of food crop species such as rice, tomatoes, and maize. An understanding of the floral meristem termination mechanism discovered in this study will benefit crop yields for food production globally.



from ScienceBlog.com https://ift.tt/3zB3Cye

Comments

Popular posts from this blog

Wiggling worms suggest link between vitamin B12 and Alzheimer’s

Worms don’t wiggle when they have Alzheimer’s disease. Yet something helped worms with the disease hold onto their wiggle in Professor Jessica Tanis’s lab at the University of Delaware. In solving the mystery, Tanis and her team have yielded new clues into the potential impact of diet on Alzheimer’s, the dreaded degenerative brain disease afflicting more than 6 million Americans. A few years ago, Tanis and her team began investigating factors affecting the onset and progression of Alzheimer’s disease. They were doing genetic research with  C. elegans , a tiny soil-dwelling worm that is the subject of numerous studies. Expression of amyloid beta, a toxic protein implicated in Alzheimer’s disease, paralyzes worms within 36 hours after they reach adulthood. While the worms in one petri dish in Tanis’s lab were rendered completely immobile, the worms of the same age in the adjacent petri dish still had their wiggle, documented as “body bends,” by the scientists. “It was an observa...

‘Massive-scale mobilization’ necessary for addressing climate change, scientists say

A year after a global coalition of more than 11,000 scientists declared a climate emergency, Oregon State University researchers who initiated the declaration released an update today that points to a handful of hopeful signs, but shares continued alarm regarding an overall lack of progress in addressing climate risks. “Young people in more than 3,500 locations around the world have organized to push for urgent action,” said Oregon State University’s William Ripple, who co-authored “The Climate Emergency: 2020 in Review,” published today in Scientific American. “And the Black Lives Matter movement has elevated social injustice and equality to the top of our consciousness. “Rapid progress in each of the climate action steps we outline is possible if framed from the outset in the context of climate justice – climate change is a deeply moral issue. We desperately need those who face the most severe climate risks to help shape the response.” One year ago, Ripple, distinguished profess...

Ancient Shell Sounds

Abandoned at the mouth of your shelter you quivered apprehensively at our approach, crying out to be held as we proclaimed the exception of your discovery. Sighing wearily as we consigned you to the dusty silence of our archives. But now When I hold you in my hands, I see the face of your purposefully speckled complexion. When I lift you to my ear, I hear the sound of an ancient sea lapping at your shores. When I place you at my lips, I feel the heartbeat of your creator pulsing to my breath. I close my eyes, as you call out to all that you have lost. The shell that was recovered from the Marsoulas cave in the Pyrenees of France (Image Credit: C. Fritz, Muséum d’Histoire naturelle de Toulouse). This poem is inspired by recent research , which has discovered that a large seashell that sat in a French museum for decades is actually a musical instrument used around 18,000 years ago. In 1931, researchers working in southern France unearthed a large seashell at the entr...