Conclusions on c-ml; outline of bz-ml; begin c-m2. I. Review of previous discussion: 1. Considered the orig'n of mutable c from norm&l C, 2. Reviewd the evidence sung ssting to thelocus of the normal C, that it arose from transposit?on of Ds 3. Discussod changes in state of c-ml: The ratio of mutat&ons to CI to dicentric forming events at Ds. ,!r. Considered the rn"p a~dcning of this with regard to action of Ds whe e no phenot2mi.c changes other than dicentric -To-fixation c0vl.d be obc~ved. 5. Conclusion drawn that the number of chan,yes at a mut.able locus may not be revcnled by study OS one type of chanse --%,the mutati-n, for exxmle. Ctncr ch:::ng3s occur -- "hidden mut?Ltions", fl- i 'L 'Jr.s &+~L~Q,u= ". 6. The stability of the changed sta-tes: 'ihose Fi;ivin,y Izigh ~Ltio of mutation to C a-:&e muci-t more st ble in action in subsec7uent gener:lti:ns than thor:e giving high ratio 0 f diccntric foxlations at c-ml, 7. The stzxtes o? many mutable loci of coxside?ahle presence of hi:den mutations suspected or revealed in will aprl :zj :5r as the discuss<::n continues, II. Continua-tion of dr'scussion of beh:svior of c-ml. of February 11, 1. Origin of stable c from c-ml - mm im~3ortance. The man;7 casts. These Begin pate 7 of outljjne xhe action of %c on c-ml and Ds when ir same cell ;: The ccntrol of AC on time and place of `mutk.ticns: Stabilized-Ac. 3os3.;Tes; L\ b -at w--.w Cl %-vL4L,~~ FQ (y&wd.&td tid wht*u L ri * -__.--__ .-___-- .- Tae origin and behavior of bz-ml I. Kernel ';;- y-ii-g mutatj..oils to Sz first noted in cross of: a>. lithe an:] e -J -iq cL~u.nce of this kernel: Bz .;;Tx. Also, C sh bz Yx back,yround with a-Fe-is of aY?eas of wx noted in the non-57 areas. Like I"r original c-ml kernel, in t?lis respect. + b). The study proved that a mutable bz loctis present in a C sh Bz clxx1:~2o some. :;Tx \;; . $ Proba:.ly app33r d because of a crossover, I to Bz, C Sh bzm'l ,,. vi.m&hq - houJ" i`u g&J.-r&k, p&g (t> LJ., It-s. eL&&: $ 2. The mutations pr&cd to be AC controlled. -`r A3- , Tip-: (p&t& @Jo ybb-lG: linlca>ye to sh and ratios in sh class: _ Photo of ear illustrating _ i: d/. q)&l@ &J C Sh Bz" Wx AC C sh bz wx ds ac female x C sh bz-ml wp; ac 4 The gametes: Sh' bzS '- -- 2. . I. History of the oripin mzst begin with original plant that underwen': the chroinoscme t&e of breakage-fusi.on-breige cycle. 1. Grigin of this plant: 4. "he cross: _._- 8 % b). The kernel selected: &roken chro-mosome from male and female: & 1 b$ &. d 'b-diul w +- w cl "..{ f&c&&&-c) ~i-Ldi L@L/ f;m 4-%& 4. The plant from t-is kernel: Number 42-B. Gin stalk and tiller self-polli nated: -@~ cytology of the tiller: The genetic costitution xi tin enc?l chr: y/ e.--.--- y ,(.. _. ._ --- o- Yy$ I %LR&* 2. The seedlings from the kernels on selfed ears: Plain slalk: All seedlings green, 'Lhe tiller: some ksrnels derived from C class showed varie,gat pale-green to green. nfor Proved to be: 6 ww e h o ? 3. Plants groom from these seedlings -- both var. and green, in field under culture number 3592. .+wp"~* 4. Yhe green :>lants se2f-poll.inatedfl 0 The variegated plants too :Jeak. ')- 5'. Ap>>earance of kernels on thenears: segregating. Mew mutables ap eared to be 'I'hese were, (1) white to yellow endosperm (2) altered starch coi?stistcnc:: -- like wx to Jx and ;ix to wx but staining showed all Vx, (3) Dicentric breaks -- like Ds-f.1. 6, Kernels on self-pollinated- ear of one plant, 3592A, showed var. for starch consistency. .a) . The constitxtion of ch;-omosomes 9 in t?is plant: c"@% e----+-w Plants from 2 -PA T./The I 91x kernels grown in following summer under culture no. 4000 A 'Lhe C>x kernels we: e in B of t'.:is culture. 8, Various tests ma6.e 7;it. these plants; One was to self-pollinate i%e ears and to cross to c sh Bz wx plants. The appearance of the kernels on the ear derived from self-pollination of 4000B-2 one Of 'i;heSC3 plai-lts: Variegated kernels and the non-variegated kernels: One-fourth of tl;e kernels were colorless and the majority of them showed speckles of color. In cross to c sh wx T-?lants, c wx, non-variegated kernels and kernels wit areas of color in a colorless background appe,:red. The type of color produced in the diY'~rent areas differed ma?.~kedly from that produced bp c-ml. The cro:>ses to plants carrying C, no variegated keynels appeared. Apneared, tne efore, t'lat a new muta~ble c, derived ;Irom a previously normal C locus had been produced. II. The tests of this new mutable c, designated c-m2, 1. Plants grown from the various types of kernels on the Belf-pollinated ear and on the ear derived f&em the cross to c sh wx* plants derived from the 2. Tests made. The cro. ses of the/variegated kernels on the celf- pollinated ears: al . Self-pollinated: Acain, ?-mjoritg of kernels showed so-r%e color. This as small specks of color and not too m.an;gT of them. b). In crosses to c'sh xx: -'early all 0.C the k:;rnels we:?e variegrted but the patches of color were much--larger than on the self-pollinated ear. The types of color patehes were not all alike. ii wide ran-ge in intensity of color and in its distribution wit-:?in a colored area. 4. The male game-tes -- cm2 sh Xx. On ears, a few areas of wx seen in the majority of the c to C varieg?+ted kernels but not xany of' them, d). The behavior very much resembled a mutable that was AC controlled, 3. The tests for AC -- these conducted. as was c-ml, hz-ml. c-1712 proved to be AC ccntro1.lcd differed, The same AC in its action altxough the derivation Plant 4OOOB-2 was AC/AC in constitution: c- ql2 a1nBz wx AC c Bh Bz Nx Ac III. The tEe of variegation produced by c-m2, prpr constitutions -- red s 1 General: shades. 1. Areas dth very pale pink colcr to those with 3arilv deep color. 2. Areas th::t seem to resemble in all ways th,? t nroduced 'bv L, norm31 C 3. In the deeper lsink areas, that produced by a-paint-brush: the color distrubution peculiar: Like 4.. These never present in tine normal C are::s, /-> i m ",I 5. The pink-type mutations: form a quantitative s ries, from almost no color to very deep color but clearly distinguished from tixose havln$ the normal C phezot;FTe, ' 2. The details of t is v:riegzti-n' Tne bo f rders bet;,reen a pink and a regular CtTme area: , ,,* _F-- .___ ,,' . "\ Iqortant: The sharp border between the Dink and the colorless a-?eas. The sharp border bet:,:een the ?3 and the colorless area, 3. The pink areas: Sometimes the following seen: / In sme 73ink arcas, section with deeper pink diffusing into light pink sector, but wit'lin the r:ink sector. rink area sharp, Gradient of color c':ange. Borders of as if mutation nresent in a sector bordering the pink area thnt -;rod&es substance tha.t the cel.ls in pink increase pigment. ("ubstance 2). 3 e C 7; 0 T can use to having it but the Tnis mutation Droduces no color in cells occurred. action in the pink sec<;or reflec'&s that such a mu.kytion It, The colored areas r sembling normal C: A section on border o.?' such a color of the sector: sector can show deep color gra$ing fnto lieye, also, Isoks as if a sector mutant C area, 'Lixis mulntrcn dot:: with a mutetion is present to left of its prerence revealed by the border. not produce any detectible color, but to _incrcase its pigment. Tne C ccXl$ can utllLze t .is zu'bstC.?ii?Ce (?his si subtance 2,) iXiy be a very li$:~t pink, but"n0 color seen, The "hidden" mut?tfon 5. Conclusions so rsr on muta5_;ons at c-m&I, a>. `TWO iTElill classes Of visible mutatlcns: 'Se "pink" sectors with very re:'nt cc lop series dcrkf:r colors, to those wit:: quP$edecp- color. p 5. 'h' e s In'tSe tl:c @aint-brush ILIke distribution of pigz-ent cvcr al.cu:>one layer is evic'ent, -.. b). The reg,:cl:r C t:;me mutation, dere, the color is only present in quantitative series also, s,mcoth wit&In the sector in ccntr&t to paint-bras- t;?)e OF mutants in pink seri-s, incrc~2ne Subs-Lance I. uroduccd by pink, can be used by the C mutant cel:!.s to their color, sub stance 2 , prodljced b:;- "C" rrec.s, incrase tilcir color, can di_'Tus:e into -pink cress and d) . `iile Gdden mutat,ions -- Production 02: eitl-lez-+ sub in sector in wI:ich no color c:z.n I?e seen, sti~.nce 1 or s~'~~~s~~:-~ilce 2 IV. The tests conducted to substF.ntiate of dii'fuslible su!r&onces, the above cca.c].:-.sic ns.or; tile production dif&sible 1. Tg&2: Y'he/subst?nces produced bTT these mu-;;atLc:ns at c-:Q ten be used b;rs normal C carq-in,g cells to increase tlleir pigmentai;ion, '%e cocstituti~n of t:r, c: kernels examined: lm\l wx c-m&y c-e / c 3x Ds AC AC ac The control: c vm ,' c xqx / C Nx Ds, AC AC AC: The observatic! s show th-mt two t-y--.es of mutations occur at c-m.2: yo "pink ii $:ic:, produces substance 1, allowing normal C carqing cells to incre se %<:!ei--: color, diff'usibl.e s-0.3- '-m and to full C tpe, that hrls no cwxt:5bution of' a ,.,,nr.e to the cel1I.s caryrinz Se EOiTl.21 C, Test 2 The geryinal pink mut;,?t?cns: ( Zelatirely stzble in ~~~ci'cnce of AC:- , _ _ . ..` .,-I -9 .-- The cross: pink-carrplng mutant :-lant x ($-y:.-.c------- / ;+ \ 3 -..-+------- 4 v ! . 4 '\ '_rc' / The kernels exax~ned, from tile mzle pa:-ent. t?ase Y:_i_ch 5ave rcceivecl a newly broken end &lJ tp;is broke:? chrwzosorne xY.lII behave in the develop5ng kernel: Comprisozs 0, f th? color patt::rns ?roduG.ed.by two crosses desc:qibcd: /' ,A '\ Co~:cluslon: The geplilriilal pip-k mutant is l?rodv.ce soxe suostmce - sx:%si:ance 1 that the normal C cal37-,ing cells call use to increase color but, these normal C carr:iLng cel?s also pl*oduce substance that the ,~exxina?- pink mutmts can use. Tnel-e am no sharp borders in any of the sect03 p:>odv.ced t~~rou~~'h the brea~ag-~3lon=brid~e cyc'es. F 3 Test Gerxinal nink mutatj.ons selected. csed as females in cxsses -"1-m--- /^ - .__. s ur.a^.ebhb. with plants ca?ry~n,~ C-ITit,. The AC AC korncls: - Nutctrl.cns to full C at c-ml occur late, to produce speckles with t"lis dose of AC, The specks of color all h ave exceedinglg deep centers, surrounded by a diffusi::n rim, the color gradually fad.ing into that of tl:.e yink bacQround. Tests for subsL&ces 1 and 2.. V. The color p:eoduced by various doses of C, Qmntitative -- ::i,gher the dose, the deeper the color: ccc c c c c c c c cccc &..y-. ---_ ___- t c ' z- __.-...-_. 'F c- -9- 2. The quantitative action of C, and the tests of Qxrease in color produced by substance 1 xI?en only 1 c present, suggests that the nomal C color produced by diffc-Brent doses of C reflect tha a&unt of substance 1 that is uyesent and p:-educed by this C gene. a). 1 c. Pink rnutant can greatly intensify tr?_e cola:? produced in cells with It often resembles the i?F?hest intensity produced by the dos,?F!e ::i:udies. Conclusions : Botn substances 1 and su::s?.rnces 2 can be produced xit3out color appearing -- see kernel ig3es. In"pink mutant8, substance 1 present in excess. dome 0t'r:cr factor limiting, this may be substance 2, In the"- C t:+es I' substance 1 produced, , pos;liblp the quantitative grades reflect the amonnt as the lig!>t colore and t3e dark colors are present. $.fferences ty-oe of mutant also shown by the pattern of color d-istributicn within each sector or in the geminal xut::tixs -- the "naint bmsh'i pattern vers the sme%& pattern, Quantitative actions witl--Lin the "pinkff :zeries: Yhe b~eakn,~e-fusion-bridge c:~clcs. c / broken piti One, two and three doses OP pTnlr -- increased color intensity, VI. The stability of the mutants produced by C-IQ. Of 1. A number of a;>?arentlp s'cat:le c ty-oes recovered, AC* Stable in presence of 2. The pink mutants -- show consideral:le stability with AC, but new alterations or mutations mise, as sectors, or as geminals. 8. The mutants Of ?ink, in absence of AC, ax! stable. 4. The full C mutants -- prob:Tl-,ly stable, but tests insuPf?cient, SC VII. The States of c-m2, 1, Griginal state -- many hidden mutatrons; ",' : many rnu-~~-~t~ons to pizk series. 2, Chanped state -- the ,mu-bations to dark pink and to full C very frequent. The Ilidden class much reduced, 'photo of ear.