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Current Affairs 2017

Tarell Alvin McCraney received PEN award for best mid-career playwright

The playwright who inspired the Oscar-nominated movie Moonlight has won a prize from PEN America, the literary and human rights organization. Tarell Alvin McCraney received an award for best mid-career playwright, PEN announced on Wednesday. McCraney’s In Moonlight Black Boys Look Blue is the basis for the acclaimed movie drama, which is up for eight nominations at Oscars.

Employment News

192 Pet PI ASC Pin-905192 C/o 56, Jhansi invites applications for Fireman 09 posts (UR-07, OBC-01, SC-01) Refer website or Employment News dated 18-24 Feb 2017...

Human Genome

The human genome is the genome of Homo sapiens, which is stored on 23 chromosome pairs. Twenty-two of these are autosomal chromosome pairs, while the remaining pair is sex-determining. The haploid human genome occupies a total of just over 3 billion DNA base pairs. The haploid human genome contains ca. 23,000 protein-coding genes, far fewer than had been expected before its sequencing. In fact, only about 1.5% of the genome codes for proteins, while the rest consists of non-coding RNA genes, regulatory sequences, introns, and (controversially named) "junk" DNA

The Human Genome Project (HGP) produced a reference sequence of the euchromatic human genome, which is used worldwide in biomedical sciences.

Genes

Surprisingly, the number of human genes seems to be less than a factor of two greater than that of many much simpler organisms, such as the roundworm and the fruit fly. However, human cells make extensive use of alternative splicing to produce several different proteins from a single gene, and the human proteome is thought to be much larger than those of the aforementioned organisms. Besides, most human genes have multiple exons, and human introns are frequently much longer than the flanking exon.

Human genes are distributed unevenly across the chromosomes. Each chromosome contains various gene-rich and gene-poor regions, which seem to be correlated with chromosome bands and GC-content. The significance of these nonrandom patterns of gene density is not well understood. In addition to protein coding genes, the human genome contains thousands of RNA genes, including tRNA, ribosomal RNA, microRNA, and other non-coding RNA genes.

Regulatory Sequences

The human genome has many different regulatory sequences which are crucial to controlling gene expression. These are typically short sequences that appear near or within genes. A systematic understanding of these regulatory sequences and how they together act as a gene regulatory network is only beginning to emerge from computational, high-throughput expression and comparative genomics studies. Some types of non-coding DNA are genetic "switches" that do not encode proteins, but do regulate when and where genes are expressed.

Identification of regulatory sequences relies in part on evolutionary conservation. The evolutionary branch between the human and mouse, for example, occurred 70–90 million years ago.

So computer comparisons of gene sequences that identify conserved non-coding sequences will be an indication of their importance in duties such as gene regulation.

Another comparative genomic approach to locating regulatory sequences in humans is the gene sequencing of the puffer fish. These vertebrates have essentially the same genes and regulatory gene sequences as humans, but with only one-eighth the "junk" DNA. The compact DNA sequence of the puffer fish makes it much easier to locate the regulatory genes.

ory gene sequences as humans, but with only one-eighth the "junk" DNA. The compact DNA sequence of the puffer fish makes it much easier to locate the regulatory genes

Other DNA

Protein-coding sequences (specifically, coding exons) comprise less than 1.5% of the human genome. Aside from genes and known regulatory sequences, the human genome contains vast regions of DNA the function of which, if any, remains unknown. These regions in fact comprise the vast majority, by some estimates 97%, of the human genome size. Much of this is composed of:

Repeat elements.

Tandem repeat: Tandem repeats occur in DNA when a pattern of two or more nucleotides is repeated and the repetitions are directly adjacent to each other.An example would be:
 A-T-T-C-G-A-T-T-C-G-A-T-T-C-G
in which the sequence A-T-T-C-G is repeated three times.

Interspersed repetitive DNA is found in all eukaryotic genomes. Certain classes of these sequences propagate themselves by RNA mediated transposition, and they have been called retrotransposons.

Transposons

The major difference of class II transposons from retrotransposons is that their transposition mechanism does not involve an RNA intermediate. Class II transposons usually move by a mechanism analogous to cut and paste, rather than copy and paste, using the transposase enzyme. Different types of transposase work in different ways. Some can bind to any part of the DNA molecule, and the target site can therefore be anywhere, while others bind to specific sequences. Transposase makes a staggered cut at the target site producing sticky ends, cuts out the transposon and ligates it into the target site.

Junk DNA

However, there is also a large amount of sequence that does not fall under any known classification. Much of this sequence may be an evolutionary artifact that serves no present-day purpose, and these regions are sometimes collectively referred to as "junk" DNA. There are, however, a variety of emerging indications that many sequences within are likely to function in ways that are not fully understood. Recent experiments using microarrays have revealed that a substantial fraction of non-genic DNA is in fact transcribed into RNA which leads to the possibility that the resulting transcripts may have some unknown function. Also, the evolutionary conservation across the mammalian genomes of much more sequence than can be explained by protein-coding regions indicates that many, and perhaps most, functional elements in the genome remain unknown. The investigation of the vast quantity of sequence information in the human genome whose function remains unknown is currently a major avenue of scientific inquiry.

Author: Dr. Sujata Roy
Assistant Professor,
Biotechnology Department.
Rajalakshmi Engineering College, Chennai

Padma Awards 2015

Padma Vibhushan 2015Name of the Awardee Discipline Shri L. K. Advani Public Affairs Shri Amitabh Bachchan Art Shri Prakash Singh Badal Public Affairs Dr. D. Veerendra Heggade Social Work Shri Mohammad Yusuf Khan alias Dilip Kumar Art Shri Jagadguru Ramanandacharya Swami Rambhadracharya Others Prof. Malur Ramaswamy Srinivasan Science and Engineering Shri Kottayan K. Venugopal Public Affairs Shri Karim Al Hussaini Aga Khan (Foreigner) Trade and Industry Padma Bhushan 2015Shri Jahnu Barua Art Dr. Vijay Bhatkar Science and Engineering Shri Swapan Dasgupta Literature and Education Swami Satyamitranand Giri Others Shri N. Gopalaswami Civil Service Dr. Subhash C. Kashyap Public Affairs Dr. (Pandit) Gokulotsavji Maharaj Art Dr. Ambrish Mithal Medicine Smt. Sudha Ragunathan Art Shri Harish Salve Public Affairs Dr. Ashok Seth Medicine Shri Rajat Sharma Literature and Education Shri Satpal Sports Shri Shivakumara Swami Others Dr. Kharag Singh Valdiya Science and Engineerin ...

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What is the Indo-US Civilian Nuclear Deal?

India and the United States signed a landmark deal in October 2008, which allows India access to US civil nuclear fuel and technology. What is it that makes this deal so significant? How does India stand to gain from it ? Here are some answers to these questions : What is the Indo-U.S. Civilian Nuclear Deal ? This is a deal between India and the United States for civil nuclear cooperation. Under this agreement, the United States can sell civilian nuclear fuel and technology to India. India in turn, has to separate its civil and military nuclear facilities and place all its civil nuclear facilities under International Atomic Energy Association (IAEA) inspection. The accord took three years to be finalized, during which it went through a series of complex stages that included amendment of U.S. domestic law, formulation of a civil-military nuclear separation plan in India, an India-IAEA safeguards (inspections) agreement and the grant of an exemption for India by the Nuclear Suppliers' ...

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History of Indian Cinema

India's first film "Raja Harischandra", a silent movie was first screened at Bombay's (Mumbai) Coronation Theater on May 3, 1913. It was made by Dadasaheb Phalke, the father of Indian Cinema. It was Phalke who introduced India to world cinema at a time when working in films was restricted by social customs. After the success of his film 'Raja Harishchandra', several filmmakers in Bombay and Madras began making silent films. By the mid 1920s, Madras had become the epicenter for all film related activities. Raghupathi Venkaiah Naidu, S S Vasan, A V Meiyappan set up production houses in Madras to shoot Telugu and Tamil films. The silent era came to an end when Ardeshir Irani produced his first talkie, 'Alam Ara' in 1931. If Phalke was the father of Indian cinema, Irani was the father of the talkie. The talkies changed the face of Indian cinema. Apart from looks, the actors not only needed a commanding voice but also singing skills, as music became a defining element in Indian cinema. The ...

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Career Scope in Advertising Industry

Advertising world has led to the emergence of many new roles within the advertising profession. In the new edge of ad world, advertising goes beyond its conventional approach. For the non-conventional and conventional advertising approach, Industry requires well groomed people who can develop innovative and creative new idea. Flexibility and competence is must for the industry as the Ad World is highly creative as well as dynamic. Advertising careers are diverse and can run across a variety of departments, offering positions in the fields of creative departments, production, media, and research. The ultimate goal is to meet the client’s goals of increasing sales as much as possible. Public relations services are often involved with businesses, governments, and institutions and can help them make effective decisions. Students of an advertising school may choose to pursue a career as a: Advertising Media PlannerMedia ResearcherCreative DepartmentCopywriter/IllustratorAccount PlanningPr ...

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