病理學(xué)含口腔病理學(xué)

1、病理學(xué)(含口腔病理學(xué)),,,陳玉昆副教授: 高雄醫(yī)學(xué)大學(xué) 口腔病理科 07-3121101~2755 yukkwa@kmu.edu.tw,Genetics (2),基因?qū)W (2),Understanding:ChromosomesMitosisMeiosisDNA, RNA, protein (transcription, tr

2、anslation),學(xué) 習(xí) 目 標(biāo),Oral Pathology for the Dental Hygienist. Olga AC Ibsen, Joan Anderson Phelan, 4th edition, 2004, p. 216-45 陳嘉芬 現(xiàn)代遺傳學(xué) Chapter 2-6, p. 25-92http://ccms.nut.edu.tw/~juang/JRH/Amino.htmwww-rohan.sdsu.ed

3、u/~sepa/genetics.htmhttp://ehrweb.aaas.org/ehr/books/2_dominant.htmlhttp://library.thinkquest.org/06aug/00440/superbibliography.htmlTarjan I, et al. Early prosthetic treatment of patients with ectodermal dysplasia: A

4、clinical report. J Prosthet Dent 2005;93:419-24www.genetic-programming.org What you need to know about cancer. Sci Am 1996;289:28-119Gibbs WW. Untangling the roots of cancer. Sci Am 2003;289:56-65Bowden JR, et al. DN

5、A microarray technology: insights for oral and maxillofacial surgeons. Br J Oral Maxillofac Surg 2004;42:542-5Kuo WP, et al. Microarrays and clinical dentistry. JADA;2003;134-456-62Ralf D. The first discovery of DNA. S

6、ci Am 2003;96:320-8www.estrellamountain.edu/faculty/farabee/biobk/BioBookglossL.htmljuang.bst.ntu.edu.tw/BCbasics/Amino1.htmwww.counterbalance.net/cqmedia/chrom-body.htmlwww.knowledgerush.com/kr/encyclopedia/Chromoso

7、me http://images2.clinicaltools.com/PageReq?id=565:1873,References for genetics (1) and (2):,參考資料,Genetics,Chromosomes,Refs. 1, 4,All living cells contain information which tells them how to develop. This information is

8、 contained in chromosomes, inside the cell nucleus, encoded in genes.,Genetics,Chromosomes,What is a chromosome? Chromosomes: Tightly coiled microscopic structures made up mainly of DNA, which consists of four different

9、 building blocks called bases (A, T, C, G). The four bases are repeated millions of times to form each chromosome,Refs. 1, 4,A chromosome is, minimally, a very long, continuous piece of DNA, which contains many genes, re

10、gulatory elements and other intervening nucleotide sequences. In the chromosomes of eukaryotes, the uncondensed DNA exists in a quasi-ordered structure inside the nucleus, where it wraps around histones (structural prote

11、ins), and where this composite material is called chromatin,Genetics,Chromosomes,Human chromosomes range in length from 50 million to 263 million bases. With few exceptions (e.g., red blood cells), each of the trillions

12、of cells in the human body contains a complete set of chromosomes--the genome. If all the bases in the human genome were spread out 1 millimeter apart, they would extend from Memphis (孟斐斯 - 美國田納西州) to Los Angeles (洛杉磯 -

13、美國加州),Refs. 1, 4,http://tw.sports.yahoo.com/nba/nba_teams.html,Genetics,Chromosomes,Refs. 1, 17,During mitosis (nuclear division), the chromosomes are condensed and called metaphasic chromosomes. This is the only natural

14、 context in which DNA is visible with an optical microscope,Genetics,Chromosomes,Refs. 1, 17,Prokaryotes do not possess histones or nuclei. In its relaxed state, the DNA can be accessed for transcription, regulation, and

15、 replication Chromosomes were first observed by Karl Wilhelm von Nägeli in 1842 and their behavior later described in detail by Walther Flemming in 1882. In 1910, Thomas Hunt Morgan proved chromosomes to be the ca

16、rriers of genes,Genetics,Chromosomes,Different stages of DNA condensation Single DNA strand Chromatin strand (DNA with histones) (3) Condensed chromatin during interphase with centromere (4) Condensed chromatin duri

17、ng prophase (5) Chromosome during metaphase,Refs. 1, 17,Genetics,Chromosomes,Refs. 1, 17, 18,1. Chromatid. One of the two identical parts of the chromosome 2. Centromere. The point where the two chromatids touch,

18、 and where the microtubules attach 3. Short arm 4. Long arm,Genetics,Chromosomes,Refs. 1, 4,The complete set of chromosomes in the cells of an organism is its karyotypeThe karyotype of the human female contains

19、23 pairs of homologous chromosomes: 22 pairs of autosomes (any chromosome that is not a sex chromosome) 1 pair of X chromosomes The karyotype of the human male contains: the same 22 pairs of autosomes one X chromos

20、ome one Y chromosome,Genetics,Chromosomes,Refs. 1, 16,Genetics,Chromosomes,The chromosomes in other living organisms differ,Refs. 1, 4,Genetics,Chromosomes,Refs. 1, 17,Chromosomes in different species,Genetics,Chromosom

21、es,Refs. 1, 4,Gene-expression profiling is screening large numbers of genes to see whether or not they are active under various conditions. When a gene is expressed, it makes a transcript (抄本),Genetics,Chromosomes,Refs.

22、1, 17,Chromosomal aberrations (1) The malfunction of either the chromosomal segregation or the crossover can lead to severe diseases. They can be divided into two classes: Chromosomal aberration or Partial chromosomal

23、dysplasia (malformation), which are usually the result of a defective crossover,Genetics,Chromosomes,Ref. 17,Chromosomal aberrations (1) Examples are: Cri du chat syndrome, which is caused by the deletion of part of t

24、he short arm of chromosome 5. Victims make high-pitched cries that sounds like a cat. They have wide-set eyes, a small head and jaw and are mentally retarded. Wolf-Hirschhorn syndrome, which is caused by partial deleti

25、on of the short arm of chromosome 4. It is characterized by severe growth retardation and mental defect.,Genetics,Chromosomes,Refs. 2, 17,Chromosomal aberrations (2) Missing or additional chromosomes, called aneuploidy

26、, which are the result of an incomplete chromosomal segregation, many of which are associated with cancer (Duesberg hypothesis). Example:Down syndrome (extra chromosome 21). This is also known as mongolism or trisomy 21

27、. Symptoms are decreased muscle tone, asymmetrical skull, slanting eyes and mental retardation,Genetics,Chromosomes,Refs. 2, 17,Chromosomal aberrations (2) Klinefelters Syndrome (XXY). Men with Klinefelter syndrome are

28、 usually sterile. They tend to have longer arms and legs and tend to be taller than their peers. Other common symptoms are lack of emotion, fatigue, apathy and an increased tendency to develop psychiatric disordersTurn

29、er syndrome (X instead of XX or XY). In Turner syndrome, female sexual characteristics are present but underdeveloped. People with Turner syndrome often have a short stature, low hairline, abnormal eye features and bone

30、development and a "caved-in" appearance to the chest,Genetics,Normal cell division - Mitosis,Ref. 1,All cells in the body, with the exception of ova andspermatozo, and called somatic cells. Cellular divisioni

31、s achieved by mitosis during a part of the somatic cell’s life span, called mitotic cycle,Function of mitosis is to create an exact copy of eachchromosome and, through division of the original cell, distribute an ident

32、ical set of chromosomes toeach daughter cell,Genetics,Normal cell division - Mitosis,Ref. 1,Ref. 9,Normal Cell Cycle,Ref. 18,,Genetics,Normal cell division – Stages of Mitosis,,Ref. 1,Mitosis is composed of 4 stages:me

33、taphase, prophase, anaphase and telophaseIn each of these 4 stages, the chromosomes are distributed in a specific arrangement,www.lewport.wnyric.org/jwanamaker/animations.htm,www.educypedia.be/education/biologyanimation

34、s.htm,In metaphase, chromosomes stain intensely & arearranged almost symmetrically at both sides of equatorial plane of the cellThe appearance of a metaphase chromosome resemblesthe letter “X”,Genetics,Normal cel

35、l division – Stages of Mitosis,Ref. 1,http://www.johnkyrk.com/,www.biostudio.com/a_sitemap.htm,When cell division takes place, each chromosome splitsvertically at the centromere, and 46 chromatids (which now become chro

36、mosomes) form one daughter cell, while the other 46 chromatids form a second daughter cell,Ref. 18,Genetics,Stages of Mitosis,,Genetics,Normal cell division – First Meiosis,Line Up,Cross-over(metaphase),Segmentexchange

37、,,,Ref. 1,www.sumanasinc.com/webcontent/animations/biology.html,Genetics,Normal cell division – Second Meiosis,,Ref. 1,Genetics,Ref. 18,Mitosis vs Meiosis,Genetics,Mitosis vs Meiosis,Ref. 18,Genetics,Ref. 2,Genetics,Mole

38、cular composition of chromosomes – Deoxyribonucleic acid (DNA),Chromosomes contain DNA DNA contains the basic code or template that carries all genetic information The basic unit of DNA is called a nuc

39、leotide A nucleotide is formed by a N-containing base, 5-carbon sugar (deoxyribose), and a phosphate,Genetics,Deoxyribonucleic acid (DNA),,,Ref. 11,Genetics,Molecular composition of chromosomes – Deoxyribonu

40、cleic acid (DNA),,Hydrogen Bond,Ref. 1,Ref. 11,Genetics,Double helical structure of DNA showing the bases,sugar, and phosphate connect with each other,Genetics,Molecular composition of chromosomes – Deoxyribonucleic ac

41、id (DNA),Mitochondrial DNA : Found in the circular chromosome of the mitochondria Maternally inherited Passed from the mother to all her offspring regardless of sex,Genetics,Molecular composition of c

42、hromosomes – Ribonucleic acid (RNA),Ref. 1,There are 4 types of RNA:Messenger RNA (mRNA)Transfer RNA (tRNA)Ribosomal RNA (rRNA)Heterogenous RNA (hnRNA)RNA can be found in both the nucleus and cytoplasm of a cell,G

43、enetics,Molecular composition of chromosomes – Ribonucleic acid (RNA),Ref. 1,mRNA: blueprint of genetic DNA for the coding of proteinstRNA: carries message for DNA to ribosomes in cytoplasm, in which prote

44、ins are producedrRNA: transfers amino acids from cytoplasm to mRNA, positioning amino acids in proper sequence to form polypeptides and hence proteinshnRNA: found within nucleus (precursor o

45、f mRNA),Genetics,Transcription of DNA to RNA to protein,When genes are expressed, the genetic information (base sequence) on DNA is first transcribed (copied) to messenger RNA in a process similar to DNA replication. mRN

46、A then leave the nucleus & enter the cytoplasm, where triplets of bases (codons) forming the genetic code specify the particular amino acids that make up an individual protein. This process, called translation, is ac

47、complished by that read the genetic code from the mRNA, and transfer RNAs (tRNAs) that transport amino acids to the ribosomes for attachment to the growing protein.,Ref. 4,Genetics,Ref. 1,Transcription of DNA to RNA to p

48、rotein,,,Ref. 12,Transcription of DNA to RNA to protein,Genetics,Ref. 18,Transcription of DNA to RNA to protein,Genetics,Ref. 13,1st discoverersof DNA -double helix,Genetics,Evolution ofchromosome?,Ref. 8,Genetics,Sum