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Protein folding and trafficking is essential for normal cell function, and when it goes awry it can lead to various chronic conditions, including fatty liver disease, diabetes, and Parkinson's. The narrative of this case study follows two undergraduate students engaged in a summer research project evaluating the effects of cell stress on cell function and health in the model organism Caenorhabditis elegans (C. elegans).  During the case study, students review animal cell organelle function and then learn about endoplasmic stress and unfolded protein response. Prior knowledge needed for the case is basic animal cell organelles and their functions and use of model organisms in research. The case was designed for a flipped classroom in which students prepare in advance by taking a quiz and watching two videos; a PowerPoint animation is also included.

Inside the cell: -cell function, -interactive, functions, specialization, mitosis, aging/death, glossary

For researchers, understanding how cancer cells function differently from normal cells lays the foundation for developing treatments designed to rid the body of cancer cells without damaging normal cells.

How are the stages of mitosis related to the creation of identical daughter cells? The primary function of the stages of mitosis is to make certain that each daughter cell is genetically identical to the mother cell. The mother cell's DNA is copied during interphase. During mitosis the chromosomes condense from long strands to highly coiled structures. The two copies of each DNA strand, called sister chromatids, are physically attached to one another. The chromosomes are moved to the center of the cell and split apart in a highly coordinated fashion. The condensation of the chromosomes, the physical connection of the sister chromatids, and the precise movement of the chromosomes are all important in making sure that each daughter cell has one copy of each chromosome and is genetically identical to the mother cell.

I learned that gene expression is the process by which the information of genes is used to direct the function of cells. Gene expression is regulated in all cells because not all genes are needed all the time or under all circumstances. For example, brain cells need to express certain genes that are not needed in muscle cells, and muscle cells need to express certain genes that are not needed in brain cells. Likewise, bacteria need to express different genes depending on the availability of food and other aspects of their surroundings.

The collection of proteins within a cell determines its health and function. Proteins are responsible for nearly every task of cellular life, including cell shape and inner organization, product manufacture and waste cleanup, and routine maintenance. Proteins also receive signals from outside the cell and mobilize intracellular response. They are the workhorse macromolecules of the cell and are as diverse as the functions they serve.

The origin of viruses remains mysterious because of their diverse and patchy molecular and functional makeup. Although numerous hypotheses have attempted to explain viral origins, none is backed by substantive data. We take full advantage of the wealth of available protein structural and functional data to explore the evolution of the proteomic makeup of thousands of cells and viruses. Despite the extremely reduced nature of viral proteomes, we established an ancient origin of the "viral supergroup" and the existence of widespread episodes of horizontal transfer of genetic information. Viruses harboring different replicon types and infecting distantly related hosts shared many metabolic and informational protein structural domains of ancient origin that were also widespread in cellular proteomes. Phylogenomic analysis uncovered a universal tree of life and revealed that modern viruses reduced from multiple ancient cells that harbored segmented RNA genomes and coexisted with the ancestors of modern cells. The model for the origin and evolution of viruses and cells is backed by strong genomic and structural evidence and can be reconciled with existing models of viral evolution if one considers viruses to have originated from ancient cells and not from modern counterparts.

Possibly the most exciting use of stem cells rests on their ability to differentiate into an enormous range of healthy functioning adult cells, thereby providing a replacement source of cells to treat serious diseases. This ultimately means that virtually any disease that results in cellular and tissue destruction can potentially be treated by stem cells. Some of the conditions are particularly debilitating and these include diabetes, spinal cord injuries, retinal disease, Parkinson's disease, heart disease and cancer.

Explore some examples of specialized plant and animal cells with the Amoeba Sisters! This video explains how specialized cell structure suits their function.

Buckle up for a prokaryote and eukaryote comparison before taking a ride into a cell to explore organelle structures and functions! This cell introduction also includes the modern cell theory.

Scientists in Australia have grown the world's first kidney from stem cells - a tiny organ which could eventually help to reduce the wait for transplants. The breakthrough, published in the journal Nature Cell Biology, followed years of research and involved the transformation of human skin cells into an organoid - a functioning "mini-kidney" with a width of only a few millimetres.

Research will make the study of diseases such as Parkinson's and Alzheimer's easier, and could lead to personalized therapies for a variety of neurodegenerative disorders. The nerve cells generated by this new method show the same functional characteristics as the mature cells found in the body, making them much better models for the study of age-related diseases such as Parkinson's and Alzheimer's, and for the testing of new drugs.

The team, led by senior authors Qi Zhou and Xiao-Yang Zhao, both from the Institute of Zoology at the Chinese Academy of Sciences, took embryonic stem cells from mice and treated them to a series of carefully worked out steps that included first exposing the stem cells to testicular cells in newly born male mice. The scientists then recreated the chemical environment that sperm cells need to grow, including early development factors and sex hormones including testosterone, follicle stimulating hormone and a growth factor from the pituitary gland.

In the August 1 issue of CELL, researchers from the Gene and Stem Cell Therapy Program at Sydney's Centenary Institute revealed another function of introns, or noncoding nucleotide sequences, in DNA. They reported that gene-sequencing techniques and computer analysis allowed them to demonstrate how granulocytes use noncoding DNA to regulate the activity of a group of genes that determines the cells' shape and function.

The researchers isolated different subpopulations of human brain stem cells and precisely identified, which genes are active in which cell type. In doing so, they noticed the gene ARHGAP11B: it is only found in humans and in our closest relatives, the Neanderthals and Denisova-Humans, but not in chimpanzees. This gene manages to trigger brain stem cells to form a bigger pool of stem cells. In that way, during brain development more neurons can arise and the cerebrum can expand. The cerebrum is responsible for cognitive functions like speaking and thinking.

In order to improve the surgical outcome of these procedures and enhance patient quality of life, new and better tools are needed for esophageal reconstruction. Biostage is working on a new regenerative technology to address esophageal cancer through their pioneer Cellframe Technology. Two weeks before the surgery, stem cells are harvested from patient abdominal adipose tissue and allowed to incubate with a biocompatible esophageal implant. These cells interact and adhere to the implant and are able to respond to signals for regeneration once inside the patient, potentially restoring both the structural and functional integrity of the esophagus. These new approaches to organ implants could revolutionize resectional surgery by providing patients with functional replacements derived from their own cells.

This interrupted case study explores the role of cytoskeletal structures on human health, specifically on respiratory function, sperm motility, and female fertility. It follows the story of a couple struggling to conceive a child and the doctors working to help them. Students are presented with clinical histories, narrative elements, documentary-style videos, and microscopic evidence in order to determine the cause of the couple's infertility. Along the way, they learn about the three types of cytoskeletal elements and the roles these play in cellular biology and human physiology. The use of videos makes it suitable for the "flipped classroom," allowing students to prepare outside the classroom for the case study, which they then complete in class. An original video by the author on the structure and function of microtubules, microfilaments, and intermediate filaments is included. The case was developed for an introductory level general biology course and could be delivered during a unit on the cell structure and function. The case could also be used in a cell biology course.

23min video Cells are everywhere. They are the basic structural, functional and biological units of all known living organisms. Cells are the smallest unit of life that is classified as a living thing, and are often called the "building blocks of life". But, there's more...

All living things are made of cells. In the human body, these highly efficient units are protected by layer upon layer of defense against icky invaders like the cold virus. Shannon Stiles takes a journey into the cell, introducing the microscopic arsenal of weapons and warriors that play a role in the battle for your health.

The DNA in just one of your cells gets damaged tens of thousands of times per day. Because DNA provides the blueprint for the proteins your cells need to function, this damage can cause serious issues-including cancer. Fortunately, your cells have ways of fixing most of these problems, most of the time. Monica Menesini details the processes of DNA damage and repair.