High-resolution 3-D imaging draws new picture of Golgi's whereabouts during cell division

December 15, 2013

Resolving a fundamental question in cell biology and showing off the powers of new high-resolution 3-D imaging, NIH scientists have discovered where the Golgi apparatus, which sorts newly synthesized proteins for transport inside and outside the cell, goes when it disassembles during cell division, according to research to be presented on Sunday, Dec. 15, at the American Association for Cell Biology (ASCB) annual meeting in New Orleans.

With conventional microscopy techniques, the scientists said they could only watch as the Golgi dissolved into tiny "puncta" and an unresolvable haze. But powerful new imaging techniques allowed the researchers to follow the Golgi through its "choreographed disassembly process," which now appears tightly linked to the (ER) during , said Dylan Burnette, Ph.D., and Prabuddha Sengupta, Ph.D., and Jennifer Lippincott-Schwartz, Ph.D., of the Eunice Shriver National Institute of Child Health and Human Development (NICHD) in Bethesda, MD.

Cell division by mitosis is the complicated yet critical process by which a mother cell divides into two daughter cells. But first, the mother cell has to pack up her cellular household contents, disassembling and dividing up everything for her soon-to-be-formed daughters.

How cells manage division has been exhaustively studied for over a century and yet basic mysteries remained. Scientists knew that some organelles such as the ER are pulled apart before division but keep their tubular membrane structure intact. Other organelles such as the Golgi, go to pieces after the prophase of mitosis through choreographed disassembly.

But where does the Golgi go once it is in pieces? To answer the question, the NIH researchers started with two plausible theories: In the endoplasmic reticulum (ER)-linked hypothesis, the Golgi puncta and enzyme haze are closely held by the ER; in the non-ER-linked model, the puncta and haze float about on their own, waiting for cytokinesis when the two daughter separate and the Golgi body reappears as stacks of membrane-bound cisternae, ready to sort proteins from the reassembled ER.

Powered by their new imaging technologies, which gave them far greater resolution than previously possible, the researchers saw clear support of the ER-linked model—the enzyme haze sticking close to ER markers with the puncta clustering near ER exits.

For a second line of proof, the NICHD researchers followed up with a pharmacological-based trapping assay that showed Golgi enzymes being held tightly by the ER during mitosis. The results indicate that Golgi enzymes redistribute into the ER during mitosis, and that they must follow an ER export pathway to reform the Golgi at the end of mitosis.

This study not only resolves a basic cellular question but shows what new solutions await as these new technologies give us keener vision and sharper tools.

Explore further: Hereditary spastic paraplegia development associated with changes in endoplasmic reticulum

More information: Author will present, "High-resolution imaging of Golgi protein trafficking through the ER during mitosis," on Sunday, Dec. 15, in the 12 noon to 1:30 p.m. poster session, "Establishing and Maintaining Organelle Structure."

Related Stories

Hereditary spastic paraplegia development associated with changes in endoplasmic reticulum

September 24, 2013
Hereditary spastic paraplegias (HSP) are a group of hereditary diseases that result in progressive loss of motor function in the lower limbs, and mutations in many different genes have been implicated in disease progression. ...

New insight in how cells' powerhouse divides

September 2, 2011
New research from the University of California, Davis, and the University of Colorado at Boulder puts an unexpected twist on how mitochondria, the energy-generating structures within cells, divide. The work, which could have ...

Recommended for you

Study finds immune system is critical to regeneration

September 20, 2017
The answer to regenerative medicine's most compelling question—why some organisms can regenerate major body parts such as hearts and limbs while others, such as humans, cannot—may lie with the body's innate immune system, ...

Thousands of new microbial communities identified in human body

September 20, 2017
A new study of the human microbiome—the trillions of microbial organisms that live on and within our bodies—has analyzed thousands of new measurements of microbial communities from the gut, skin, mouth, and vaginal microbiome, ...

Immune cells produce wound healing factor, could lead to new IBD treatment

September 20, 2017
Specific immune cells have the ability to produce a healing factor that can promote wound repair in the intestine, a finding that could lead to new, potential therapeutic treatments for inflammatory bowel disease (IBD), according ...

As men's weight rises, sperm health may fall

September 20, 2017
(HealthDay)—A widening waistline may make for shrinking numbers of sperm, new research suggests.

Researchers find way to convert bad body fat into good fat

September 19, 2017
There's good fat and bad fat in our bodies. The good fat helps burn calories, while the bad fat hoards calories, contributing to weight gain and obesity. Now, new research at Washington University School of Medicine in St. ...

New model may help science overcome the brain's fortress-like barrier

September 19, 2017
Scientists have helped provide a way to better understand how to enable drugs to enter the brain and how cancer cells make it past the blood brain barrier.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.