Cell biology is the discipline that concentrate on the fundamental unit of living things. Cells are the smallest working unit in a living organism’s structure and usually have a nucleus that is surrounded by a cytoplasm and a membrane. Cell biology checks and evaluates the biological properties, composition, interactions and life at the microscopic and molecular levels. Research on cell biology throws more light to both single-celled organisms, such as bacteria and multicellular organisms, such as plants and animals.
Generally, the field of cell biology centres on how the different organelles in a cell work together, how their cell activity is controlled, and how the different cells within an organism work together. Identifying the composition of cells and how cells work together is crucial in the biological level.
In the 21st century, scientists in the field of cell biology were able to find out that plants are also put under stress. Thus, factors such as high salt and temperature concentration disrupt their physiology and under these conditions, when this happens, the plant uses complex signalling cascade.
The signalling cascade of stress in plants growing on the ground is based on finding the abscisic acid messenger substance, which is a plant hormone. The researchers found that the GUN1 hormone helps plant in their early evolution to cope with the stress they are exposed to. Such as environmental factors. Cell biology in the 21st century also helped the scientists to find that when a new plant develops from a seed and begins to grow its first leaf, the development of its chloroplasts is in a race of survival. The sunlight instead burns the plant from the inside out by generating dangerous chemicals called reactive oxygen species in the absence of chloroplasts to convert sunlight into energy.
The development of Chloroplast requires a relay of contact signals between the chloroplast development and the central DNA centre of the plant cell.
A protein called GUN1 was found by the researchers. This protein was known to play an important role in this chloroplast-core interaction, but the details of its responsibility remained uncertain. Plant cells make more GUN1 protein in their entire lives, but this protein is easily degraded by excess sunlight.
The scientists also found that GUN1 also affects the production and delivery of another communication molecule with the help of cell biology. It has been found that the protein, GUN1, binds to an iron containing a molecule called plant heme during the first days of the plant developing its leaf and times without sunlight. This plant heme is part of the chemical compounds of tetrapyrroles that are made of four pentagon rings that tie metal in its centre. Although the researchers understood how tetrapyrroles are being developed, they were unable to understand how they interact or move around the cell and what they are doing on their journeys. The researchers observed that the protein is attached directly to heme and other tetrapyrroles, thus controlling the production of heme by the cell during a series of experiments using GUN1.
To conclude, the heme which sends a signal to the nucleus is released by GUN1 only when light is available to photosynthesize chloroplasts into energy. GUN1 is one of the groups of six gene mutations, all affecting the relationship between chloroplast and nuclear genomes. The other GUN proteins also work together with other types of molecules of tetrapyrrole. With cell biology in the 21st century, researchers now hope that having identified all the GUN proteins, this can lead to a more detailed insight of how tetrapyrroles contribute to chloroplast-to-core communication.