1. Online Counseling Resource YCMOU ELearning Drive… School of Architecture, Science and Technology Yashwantrao Chavan Maharashtra Open University, Nashik – 422222, India

2. SEP-SBI074-CP02-03 Introduction Programmes and Courses SEP –SBT074- CP02-U02

3. School of Science and Technology, Online Counseling Resource… Credits  Academic Inputs by Sonali Alkari Faculty YCMOU Nagpur Centre, Faculty LAD college P.G. D of Biotechnology Research officer Ankur Seeds Pvt Ltd sonalisa_alkari@yahoo.co.in Sonalisaal@rediffmail.com 3© 2007, YCMOU. All Rights Reserved.

4. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.4 How to Use This Resource  Counselor at each study center should use this presentation to deliver lecture of 40-60 minutes during Face-To-Face counseling.  Discussion about students difficulties or tutorial with assignments should follow the lecture for about 40-60 minutes.  Handouts (with 6 slides on each A4 size page) of this presentation should be provided to each student.  Each student should discuss on the discussion forum all the terms which could not be understood. This will improve his writing skills and enhance knowledge level about topics, which shall be immensely useful for end exam.  Appear several times, for all the Self-Tests, available for this course.  Student can use handouts for last minutes preparation just before end exam.

5. School of Science and Technology, Online Counseling Resource… © 2007, YCMOU. All Rights Reserved.5 Learning Objectives After studying this module, you should be able : Explain what is RNA Describe structure of RNA State different types of RNA Explain variation in RNA structure State functions of RNA

6. School of Science and Technology, Online Counseling Resource… Introduction :RNA  Ribonucleic Acid (RNA), genetic material of certain viruses (RNA viruses) and, in cellular organisms, the molecule that directs the middle steps of protein production.  In RNA viruses, the RNA directs two processes—protein synthesis (production of the virus's protein coat) and replication (the process by which RNA copies itself).  In cellular organisms, another type of genetic material, called deoxyribonucleic acid (DNA), carries the information that determines protein structure.  But DNA cannot act alone and relies upon RNA to transfer this crucial information during protein synthesis (production of the proteins needed by the cell for its activities and development). 6© 2007, YCMOU. All Rights Reserved.

7. School of Science and Technology, Online Counseling Resource… Structure of RNA:1  Like DNA, RNA consists of a chain of chemical compounds called nucleotides.  Each nucleotide is made up of a sugar molecule called ribose, a phosphate group, and one of four different nitrogen- containing compounds called bases.  The four bases are adenine, guanine, uracil, and cytosine. These components are joined together in the same manner as in a deoxyribonucleic acid (DNA) molecule. 7© 2007, YCMOU. All Rights Reserved.

8. School of Science and Technology, Online Counseling Resource… Structure of RNA :2  RNA differs chemically from DNA in two ways.  The RNA sugar molecule contains an oxygen atom not found in DNA,  RNA contains the base uracil in the place of the base thymine in DNA 8© 2007, YCMOU. All Rights Reserved.

9. School of Science and Technology, Online Counseling Resource… Structure of RNA:3  The study of RNA structure has become important in understanding it's functions. RNA's are not simply long stands of nucleotides, the structure of RNA can be classified into three levels. Those are,  Primary structure- that is the sequence  Secondary structure- By intra strand base pairing (Watson Crick base pairing GC, AU and Wobble base pairing GC) 9© 2007, YCMOU. All Rights Reserved.

10. School of Science and Technology, Online Counseling Resource… Difference between DNA & RNA Small chemical difference from DNA, but large structural differences: Single stranded helix – ability to fold into 3D shapes; can become functional 10© 2007, YCMOU. All Rights Reserved.

11. School of Science and Technology, Online Counseling Resource… Structure of RNA:4  Tertiary structure- 3D structure, conformation.  They form intra strand base pairs leading to secondary and tertiary structures, which are important for their functions.  These base parings are between, Guanine and Cytosine (G,C) with three hydrogen bonds, Adenine and Uracil (A,U) with two hydrogen bonds and additionally, G and U pair with two hydrogen bonds to form a base pair know as wobble pair. 11© 2007, YCMOU. All Rights Reserved.

12. School of Science and Technology, Online Counseling Resource… Structure of RNA:5  There are several motifs commonly found in RNA secondary structures. Those are,  helix  hairpin loop  interior loop  buldge loop  multi loop  pseudo knot 12© 2007, YCMOU. All Rights Reserved.

13. School of Science and Technology, Online Counseling Resource… RNA Structures Vary RNA more like proteins than DNA: structured domains connected by more flexible domains, leading to different functions. e.g. ribozymes – catalytic RNA 13© 2007, YCMOU. All Rights Reserved.

14. School of Science and Technology, Online Counseling Resource… RNA Synthesis RNAP binds, melts DNA into open form nucleosides added 5’  3’ so “bottom” strand is really template 14© 2007, YCMOU. All Rights Reserved.

15. School of Science and Technology, Online Counseling Resource… RNA Structure – Types of RNA  Messenger RNA (mRNA) – genes that encode proteins  Ribosomal RNA (rRNA) – form the core of ribosomes  Transfer RNA (tRNA) – the adaptors that link amino acids to mRNA during translation  Small nuclear RNA (snRNA) – RNA splicing of pre- mRNA to Mrna  Small regulatory RNA – also called non-coding RNA 15© 2007, YCMOU. All Rights Reserved.

16. School of Science and Technology, Online Counseling Resource… Functions of RNA:1  RNA play vital roles in many cell functions. They are major components of ribosomes (rRNA) and also they are involved in in protein biosynthesis (mRNA and tRNA).  Some RNAs are involved in catalytic activities (Ribozymes).  Apart from those there are other types of RNAs which are involved in other important cellular functions.  The structure is important in performing their respective cellular functions.  Apart from three major classes of RNA there are other types of RNA which perform important cellular functions. 16© 2007, YCMOU. All Rights Reserved.

17. School of Science and Technology, Online Counseling Resource… Functions of RNA:2 Types of RNAsFunction of RNA ribosomal- rRNA mRNA translation tRNA mRNA translation mRNA transfermessenger protein translation/regulatory heterogeneous nuclearhnRNA intermediates of mRNAs small cytoplasmic -scRNA signal recognition particle, tRNA process 17© 2007, YCMOU. All Rights Reserved.

18. School of Science and Technology, Online Counseling Resource… Functions of RNA:3 Types of RNAsFunction of RNA small nuclearsnoRNA mRNA processing, poly A, histone 3' process small nucleolar- snoRNA rRNA processing/maturation/ methylation regulatory RNAs regulation of transcription and translation 18© 2007, YCMOU. All Rights Reserved.

19. School of Science and Technology, Online Counseling Resource… What You Learn…  You have learnt : RNA consists of a chain of chemical compounds called nucleotides Ribonucleic Acid (RNA), genetic material of certain viruses (RNA viruses). The RNA sugar molecule contains an oxygen atom not found in DNA, RNA contains the base uracil in the place of the base thymine in DNA RNA play vital roles in many cell functions the structure of RNA can be classified into three levels There are differrnt Types of RNAs. 19© 2007, YCMOU. All Rights Reserved.

20. School of Science and Technology, Online Counseling Resource… Critical Thinking Questions 1.Describe the structure of RNA in details? 2.Is RNA a genetic material? State the functions of RNA. 3.Types of RNA. 4.Difference between DNA and RNA © 2007, YCMOU. All Rights Reserved.20

21. School of Science and Technology, Online Counseling Resource… Hints For Critical Thinking Question 1.Structural details primary, secondary and tertiary. 2.Yes, in microorganisms like viruses. 3.mRNA, (rRNA) and tRNA 4.Chemical difference and difference in structure and functions. © 2007, YCMOU. All Rights Reserved.21

22. School of Science and Technology, Online Counseling Resource… Study Tips:1  BOOK1 Title: Biochemistry Author: JEREMY M.,BERGJOHN L.,TYMOCZKOLUBERT STRYER Publisher: W. H. Freeman and Company  Book2 Title: Molecular Cell Biology Author: Harvey Lodish, David Baltimore Publisher: W. H. Freeman and Company 22© 2007, YCMOU. All Rights Reserved.

23. School of Science and Technology, Online Counseling Resource… Study Tips:2  BOOK3 Title: Lehninger, Principles of Biochemistry Author: David L. Nelson, Michael M. Cox. Publishers: W. H. Freeman and Company  BOOK4 Title: Biochemistry Author: Keshav Trehan Publishers: Wiley Eastern 23© 2007, YCMOU. All Rights Reserved.

24. School of Science and Technology, Online Counseling Resource… Study Tips:3 www.en.wikipedia.org Microsoft Encarta Encyclopedia http://en.wikipedia.org/wiki/ Wikipedia the free encyclopedia 24© 2007, YCMOU. All Rights Reserved.

25. School of Science and Technology, Online Counseling Resource… End of the Presentation Thank You ! 25© 2007, YCMOU. All Rights Reserved.