Week 10! 10-24-2013!
Annotated Bibliography!
Sources of papers! 3 papers! Peer-reviewed scientific literature (no review articles)! No more than 2 from:! the same author! the same journal! 2 of the 3 must have been published within the last 5 years!
Contents of each annotation! Citations (not included in the word count)! Multiple Authors! Authors. Year. Article title. Journal title. Volume, Issue: page.! Jongmans, A.G., van Breemen, N., Lundstrom, U., van Hees, P.A.W., Finlay, R.D., Srinivasan, M., Unestam, T., Giesler, R., Melkerud, P-A., and Olsson, M. 1997. Rockeating fungi. Nature. Vol 389, No. 6652: 682.! 2-3 sentences about why the author(s) did the study! 2-4 sentences of background information! 3-5 sentences about primary methods and results! 2-3 sentences summarizing the conclusions! 250 words max!!
Summary of all 3 annotations! 250 words max, included after the third annotation! 1. Overall conclusion (~125 words)! Overview of combined results! Why the general issue they address is important! Could include one or more key questions that remain to be answered! 2. Your personal interest (~125 words)! What you thought was most interesting about the issue(s) addressed by the 3 papers!
Writing style! Read Writing Scientific Papers! 2 page maximum! 12 pt. Times font, single spaced, 1 margins! Include word count:! at the end of each annotation! at the end of each summary section! Final format (by page):! 1. Cover page: your name, TAʼs name, section number, date, title of topic! 2. Annotations 1 & 2! 3. Annotation 3 & overall summary! 4-7. Photocopies of the abstract and the first page of the!!introduction of each article!
Due date! Paper due Week 14 (November 21)! 1 pt extra credit if turned in (to front office) by 4:00pm Wednesday, November 6 (Week 12)! 0.5 pt extra credit if turned in (to front office) by 4:00pm Monday, November 11 (Week 13)!
Paid research opportunities! MARC Program! For underrepresented or first generation college students interested in pursuing a PhD in Biomedical Science! Applications due soon! Contact Dr. Diane Marshall! marshall@unm.edu! Office Hours: Tuesday & Thursday 12:30-1:30, Castetter 156! IMSD Program! For underrepresented students interested in pursuing a PhD in Biomedical Science! Positions open soon! Contact Lupe Atencio! latencio@unm.edu! Castetter 209! McNair Program! For underrepresented or first generation college students interested in pursuing a PhD or professional degree! Applications due in March! Contact Ricardo Romero! loborr@unm.edu! Mesa Vista 3019!
lac operon! 6/*#-+( (&($+0"(-8(3&%"*#0&'(9:;("1&"( %-+"&0+,(&(%'$,"*#(-8()*+*,($+.*#("1*(%-+"#-'( -8(&(,0+)'*(/#-7-"*#5( <1*(*=/#*,,0-+(-8("1*,*()*+*,(&#*(&',-($+.*#( "1*(%-+"#-'(-8(&(,0+)'*(-/*#&"-#5( 6/*#&"-#( (&(,*)7*+"(-8(9:;("1&"(&( #*)$'&"-#(30+.,("-5(!"#$%"$#&'()*+*,( ()*+*,(*+%-.*(/#-"*0+,(&+.( "1&"(&#*(%-2#*)$'&"*.(34("1*(-/*#-+5( <1*(!"#(-/*#-+(-8($%&#'!(&
Lactose metabolism!!"#$%&%'()'*+&'!"#%',&"&' E. coli!"#$%&%'()'*+&'!"#$',&"&' Galactoside permease -Galactosidase Glucose Lactose Plasma membrane Galactose -&*.($/012'$3'/.#*$1&'0"'&'(#)!*' ( 4.#*$1&'01'51&%'03'*+&6&'01'"$',/5#$1&'.7.0/.(/&'*$'*+&'#&//8'9*':0//'"$*'(&'51&%'03',/5#$1&'01'.7.0/.(/&8'
Video lac operon! http://www.youtube.com/watch?v=obwtxdi1zvk!
Negative regulation lac operon!!"#$%#&%#''(%$)'$*(+',),-,).#/0$'0+,"#')1#2$ Repressor present, lactose absent: Repressor binds to DNA. No transcription occurs. DNA Normal lacl gene Repressor synthesized lacl + RNA polymerase bound to promoter (blue DNA) The repressor blocks transcription lacz lacy 3+$,"#$45'#+*#$(6$/4*,('#7$,"#$%#&%#''(%$)'$5(-+2$,($,"#$(&#%4,(%$'#8-#+*#$(6$,"#$!"#$(&#%(+9$ :4,$,")'$&()+,7$2($+(,$*(+')2#%$,"#$&%#'#+*#$(%$45'#+*#$(6$;/-*('#$
Negative regulation lac operon! >+-<*0)$(+"0*# #.#)0"=-E:;#6+-&*2-&#$%.$# *+1&)#,+(#6+(&#$%."#+"&#'(+$&0"4# Repressor present, lactose present: Lactose binds to repressor, causing it to release from DNA. Transcription occurs (lactose acts as inducer). Repressor synthesized TRANSCRIPTION BEGINS -Galactosidase Permease mrna Normal lacl gene lacl + RNA polymerase bound to promoter (blue DNA) lacz lacy Lactose-repressor complex!"#$%&#'(&)&"*&#+,#-.*$+)&/#-.*$+)&#.*$)#.)#."#0"12*&(#."1#30"1)#$+#$%&#(&'(&))+(4# 5%&#(&'(&))+(#0)#(&6+7&1#,(+6#$%&#+'&(.$+(#)&82&"*&#+,#$%&#!"##+'&(+"4#9:;# '+-<6&(.)&#*."#3&=0"#$(.")*(0'$0+"#+,#$%&#)$(2*$2(.-#=&"&)#!"12*&(# #.#*-.))#+,#&,,&*$+(#6+-&*2-&)#$%.$#0"12*&)# &?'(&))0+"#+,#)$(2*$2(.-#=&"&)#3<#30"10"=#$+#.# (&'(&))+(#'(+$&0"4# @,,&*$+(#A#)6.--#6+-&*2-&#$%.$# (&=2-.$&)#&?'(&))0+"#
Positive regulation lac operon! When camp is present: camp binds to CAP and the camp-cap complex binds to DNA at the CAP site. RNA polymerase binds the promoter efficiently. Transcription occurs frequently. When camp is absent: CAP does not bind to DNA. RNA polymerase binds the promoter inefficiently. Transcription occurs rarely. camp CAP site RNA polymerase bound tightly to promoter (blue DNA) CAP CAP site CAP RNA polymerase bound loosely to promoter (blue DNA) FREQUENT TRANSCRIPTION Operator INFREQUENT TRANSCRIPTION Operator lacz lacz lacy lacy laca laca Glucose inhibits the activity of the enzyme adenylyl cyclase, which catalyzes production of camp from ATP. Glucose inhibits this enzyme ATP Adenylyl cyclase cam P Two phosphate groups!"#$%&'%()*+,%
Partial diploid cells! Operon is cis-acting! Repressor is trans-acting! ===!
trp operon!!"#$!"#$%&#'%($%)$$%&'()*&
Negative regulation trp operon! When tryptophan is present, transcription is blocked. Repressor Tryptophan Operator RNA polymerase bound to promoter No transcription When tryptophan is absent, transcription occurs. TRANSCRIPTION 5 genes coding for enzymes involved RNA polymerase in tryptophan synthesis bound to promoter!"#$%&'(%"()*+$,-$*.%,+/$*-$*+$0110.%"&$23%4$,+$%),-$.*-04$*-$*$."5&0(&0--"&6$7$."5 &0(&0--"&$2,+8-$%"$*$&0(&0--"&$*+8$&0(&0--0-$09(&0--,"+6$
Types of operons! lac operon trp operon!"#$%&'()*+,)-."************************/),-)00&'()*+,)-."* Repressor Lactose Lactose binds to repressor Repressor Tryptophan Tryptophan binds to repressor Operator TRANSCRIPTION Lactoserepressor complex releases from operator Transcription of lac operon Operator Tryptophanrepressor complex binds to operator No more transcription of trp operon
Activity! Fill out worksheet as a group! Will discuss answers as a class! I = laci (the repressor gene)! P = P (the promoter for the lac operon)! O = laco (the operator)! Z = lacz (the β-galactosidase gene)! Y = lacy (the permease gene)!! Notes:!!Inducer: Lactose!!Assume the cell is glucose-starved (high camp)!! + is wild type (functioning protein)!! - is a mutant (non-functioning protein)!! C is a mutant (constitutively active always working)!!!