The synaptonemal complex is a protein complex, which can mediate the crossing over among homologous chromosomes (Peoples,T.L. 2002). It consists of three important parts, the lateral element, the central element and the transverse element. During the leptotene stage, the SYCP2 and SYCP3 proteins form axial elements, lateral element and precursors. The SYCP1 protein contains a carboxy-terminal domain and an amino-terminal domain that are necessary for interaction with lateral and central elements, respectively.
In terms of mammalian trans genesis, electroporation is an effective method of introducing exogenous DNA into embryonic stem (ES) cells. This technique has recently, been used to transfer genes into cultured mammalian embryos at defined stages of development. It was reported that there is an increase from 12 to 19% of transgenic bovine blastocysts when electroporation was included in an otherwise passive sperm-DNA uptake protocol. Similar findings were reported, again with transgenic bovine blastocysts. Fish species were also reported to be genetically manipulated in
These move from the outer portion of the seminiferous tubule to a more central location and attach themselves around the sertoli cells. The primary sperm cells then develop somewhat by increasing the amount of cytoplasm and organelles within the cytoplasm. After a resting phase the primary cells divide into a form called a secondary sperm cell. During this cell division there is a splitting of the nuclear material. In the nucleus of the primary sperm cells there are 46 chromosomes; in each of the secondary sperm cells there are only 23 chromosomes, asthere are in the egg.
In this prokaryotic specific mechanism, termination occurs by the formation of a stem loop hairpin structure which occurs at a palindrome. Palindrome A palindromic sequence occurs where a series of base pairs in the 5' to 3' direction on the DNA or RNA strand is repeated in the inverse sequence further along the same strand. This is the termination signal for the Rho Independent Termination. These sequences are able to base pair together as the RNA strand folds over on itself to form a stem loop structure as it is being transcribes. The sequence of the termination signal is followed by a series of Adenines which transcribes to a poly-Uracil tail on RNA.
Deoxyribonucleic acid (DNA) is a molecule found in all forms of life that is passed down from parents to offspring. What makes each DNA unique is the chemical makeup of the molecule sometimes referred to as the “blueprint of life.” (BIO). DNA is made up of nucleotides consisting of a sugar, a phosphate and a base pair. About six million nucleotide base pairs make up DNA in each cell. Retrieving this amount of data is both exhausting and time consuming.
Among these, there is the nucleus that contains most of the genetic material (DNA) of the cell. Here occur the DNA duplication and the first steps in decoding genetic information. In all eukaryotic cells, there are also: the endoplasmic reticulum, the Golgi apparatus,
NAT. REV. GENETICS 8 (4), 286–298 (2007)) Histone proteins, consist of a globular C-terminal domain and an unstructured N-terminal tail. The N-terminal tail of histones can undergo a variety of changes which include methylation and acetylation. These modifications mediate and control key cellular processes such as transcription, replication and repair within the human genome.
Transgenesis is an advanced biotechnological technique by virtue of which introduction of new genes to a species belonging to an entirely different species is carried out. The transferred foreign gene is known as a ‘Transgene’. Plants in which the introduction of foreign gene or genes from another unrelated plant or even a different species have been carried out artificially are referred to as ‘Transgenic plants’ or ‘Genetically Modified Plants’. Similarly the animals in which foreign gene/genes have been deliberately inserted into their respective genomes are known as ‘Transgenic animals’ or ‘Genetically Modified Animals’. Transgenic cropping has been adapted at a faster rate than any other agricultural technology and presently is being exploited by 16 million farmers as reported by James (2011).
Bacteria taking up foreign DNA is known as transformation. Transformation implies uptake in bacterial, yeast or plant cell DNA while transfection is the term used in reference of mammalian uptake. Chemical transformation, electroporation or particle bombardment is the typical method of construct into a host cell. Conjugation: The easiest illustration is to consider this as a version of bacterial sex. In conjugation the two bacterial cells connect, and the male donates a piece of DNA to the female.
Moreover, this experiment makes me understand the role of gel electrophoresis in DNA preparation and analysis. Through the experiment of building DNA, I knew more about the composition of DNA, and the way and order of deoxyribonucleotides. Through the DNA transcription and translation experiments, I learnt that mRNA is the transmitter of genetic information. I also knew that a genetic code corresponds to an amino acid. This made me have a deeper understanding of the process from genetic information to protein.