I. FOREWORD1

II. REPORTS FROM COOPERATORS 2

albany, california and berkeley, california
It's a Gnarley One! (Gn1) --Toshi Foster and Sarah Hake 2
lethal ovule2 causes aberrant embryo sac development --Erik Vollbrecht 2
Deficiency analysis of megagametogenesis --Erik Vollbrecht 3
Loss of the dominant knotted1 phenotype by EMS mutagenesis --Laurie Smith, Randall Kerstetter and Sarah Hake 3
ames, iowa
An attempt to tag rhm with transposable elements --Ru-Ying Chang and Peter A. Peterson 4
Resistance to Helminthosporium maydis: one gene or two genes? --Ru-Ying Chang and Peter A. Peterson 5
Multiple gene loss on the short arm of chromosome 9 in C-m925408U is not induced by Ac --Vijay Thatiparthi and Peter A. Peterson 6
Genomic regions affecting plant height in maize and sorghum --M. G. Pereira and M. Lee 7
Comparative linkage analysis of RFLP loci and QTL in F2:3 and F6:7 recombinant inbreds --D.F. Austin and M. Lee 7
Cloning of sugary1 by transposon tagging with Mutator --Martha G. James and Alan M. Myers 8
Some thoughts on the nature and utilization of the Mutator system --Donald S. Robertson 8
Information on the Iowa State Mutator and other stocks from the Robertson laboratory --Donald S. Roberston 10
ames, iowa and johnston, iowa
Analysis of the 5' region of the P gene as a potential floral-specific promoter --Xianggam Li, Laura Tagliani, Bruce Drummond, Ben Bowen and Thomas Peterson 10
A new P-ww allele and Ac element with high negative dosage effect and novel suppressing activity --Jianbo Zhang and Thomas Peterson 10
bangkok, thailand
Four new tropical lowland downy mildew resistant maize populations --C. De Leon, G. Granados and R. N. Wedderburn 10
beijing, china
Origin of Chinese waxy maize (Zea mays sinensis) --Mengqian Zeng and Yannan Liu 12
Studies on the superior new germplasms in sweet corn (Zea mays saccharata) --Yannan Liu, Mengqian Zeng and Taolan Yang 12
bergamo, italy
Role of the transcriptional regulator opaque2 in carbon partitioning between starch and proteins in the sink --M. Maddaloni, G. Donini, F. Forlani, L. Stasse and M. Motto 12
RFLP mapping of QTLs for grain yield and agronomic traits --P. Ajmone Marsan, G. Monfredini, W. Ludwig, A. E. Melchinger, G. Pagnotto and M. Motto 13
Effect of sucrose and asparagine on the synthesis of storage products in in vitro grown maize endosperms --D. Bosio, C. Balconi, E. Rizzi, L. Nembrini, A. Morselli and M. Motto 14
Conditions for electroporation of intact type II maize calli --E. Lupotto, P. A. Della Torre, M. Albano and G. M. Borrelli 14
berkeley, california
The lg3 locus maps to the short arm of chromosome 3 --Yong Chi, John Fowler and Michael Freeling 16
The pleiotropic mutation dek*-Mu1364 maps to chromosome arm 9L --Mike Scanlon, Mi Chang and Michael Freeling 16
The lxm1 gene maps near position 88 on 3L --Denise Schichnes, Claudine Woo and Michael Freeling 16
bombay, india
Non-Mendelian breeding behaviour of sh1-B (shrunken1-Bombay) allele --S. Nadiger and N. K. Notani 17
Buffalo, New York
Determining the nuclear volume in a pollen grain by using laser scanning confocal microscopy and multi-dimensional image analysis --Ping-chin Cheng and J. K. Samarabandu 17
cedar Falls, iowa
Organogenesis of the maize mutant Fascicled ear (Fas) --Gretchen Haas and Alan Orr 18
chestnut hill, massachusetts
Molecular markers of anther culture-derived plants --Y. C. Ting 19
cologne, germany
The Ac transposase consists of several, functionally distinct domains --Ute Behrens-Jung, Reinhard Kunze and Sandra Kuehn 20
The DNA-binding sites of the Ac transposase --Heinz-Albert Becker and Reinhard Kunze 21
In vivo aggregation of Ac transposase in nuclei of maize endosperm and petunia protoplasts --Manfred Heinlein, Torben Brattig, Sandra Kuehn, Ute Behrens and Reinhard Kunze 22
Correlation of aggregation phenotypes and activity of mutant Ac transposase derivatives --Manfred Heinlein, Sandra Kuehn, Ute Behrens and Reinhard Kunze 22
Ac allele-specific variegation patterns are not due to modifier genes --Manfred Heinlein and Peter Starlinger 22
Dosage effects of Ds --Manfred Heinlein and Peter Starlinger 23
Studies on Ac/Ds methylation --Lihua Wang, Manfred Heinlein and Peter Starlinger 23
Characterization of the Ac sequences required in cis for transposition --Shivani Chatterjee and Peter Starlinger 23
Ectopic expression of Zmhox1b alters the development in transgenic tobacco --Bärbel Überlacker, Claudia Mehlem and Wolfgang Werr 24
The Zmhox2a/b gene pair is highly transcribed in meristematic maize tissues --Bettina Klinge, Christian Korfhage and Wolfgang Werr 24
columbia, missouri
The solid-state chlorophyll meter: a novel instrument for rapidly and accurately determining the chlorophyll concentrations in seedling leaves --Brent Krugh, Lisa Bickham and Donald Miles 25
Location of blh*-2359 on chromosome 8L --M. G. Neuffer and Dan England 27
Location of Yg*-2448 on chromosome 1S --M. G. Neuffer and Dan England 27
Bif1-pro1-Lg4 linkage on chromosome 8 --M. G. Neuffer and Dan England 27
Designation of bif2 --M. G. Neuffer and Steve Briggs 28
Another pair of factors expressing orange pericarp --M. G. Neuffer and Allen Wright 28
New mutant designations --M. G. Neuffer 28
Dominant Lesion mutants on chromosome 2 and designation of Les18 and Les19 --M. G. Neuffer and Dan England 29
Tests for allelism among dominant lesion mutants --M. G. Neuffer 29
Increasing sensitivity and reducing cost and prep time using the "modified dry blot" procedure for Southern and Northern analyses --Pamela S. Close, Darren Gruis and Kevin D. Simcox 29
Combined F2 and IF2 RFLP map --Oscar Heredia-Díaz, Jack Gardiner, Dave Hoisington, Shiaoman Chao, Ed Coe, Theresa Musket and Guilin Xu 30
columbia, missouri and athens, georgia and tifton, georgia
Silk browning, maysin content, and corn earworm resistance --P. F. Byrne, L. L. Darrah, D. J. Moellenbeck, B. D. Barry, M. E. Snook, B. R. Wiseman and N. W. Widstrom 35
Columbia, Missouri and Woodward, OKlahoma
Current status of the Tripsacum dactyloides (Eastern gamagrass) RFLP molecular genetic map --C.A. Blakey, E.H. Coe, Jr. and C.L. Dewald 35
RFLP locus-site designations for interspecific mapping of molecular markers derived from Tripsacum dactyloides and maize --C.A. Blakey, E.H. Coe, Jr. and C.L. Dewald 37
Gynomonoecious sex form1 gene (gsf1) of Tripsacum dactyloides: Description and Tripsacum linkage map location --C.L. Dewald, C.A. Blakey and E.H. Coe, Jr. 38
columbia, missouri and wooster, ohio
Three genes control resistance to wheat streak mosaic virus in the maize inbred Pa405 --M. D. McMullen, M. W. Jones, K. D. Simcox and R. Louie 38
DEFIANCE, OHIO
When does paramutation take place? --Bernard C. Mikula and Beth Besaw 38
Clonal pattern of pigmented cells in aleurone is host- determined in the second week of seedling development. --Bernard C. Mikula and Beth Besaw 39
Host-controlled timing of clonal-pattern expression in the third week of seedling development --Bernard C. Mikula and Beth Besaw 39
Durham, north carolina
Rootworm Resistance in F1 Tripsacum X Zea diploperennis --Mary Eubanks 40
Eugene, ORegon
Isolation and genomic mapping of cDNAs encoding the chloroplast Rieske Fe/S protein: two unlinked genes are transcribed in maize --Alice Barkan and Macie Walker 41
Mapping and allelism results: nuclear mutations affecting chloroplast biogenesis --Alice Barkan, Rodger Voelker, Melanie Johnson, Lisa Cipolla and Laura Roy 41
Gainesville, FLorida
A summary of the chromatin structure and other architectural features of the maize Adh1 5' flanking region --Anna-Lisa Paul and Robert J. Ferl 41
Brain protein homologs and gene names --Robert Ferl, Nick deVetten, Guihua Lu, Paul Sehnke, Christine Daugherty, Beth Laughner and Ke Wu 41
GiF/Yvette, France
A composite map of expressed sequences, based on four individual maps. --Mathilde Causse, Catherine Damerval, Alexandrine Maurice, Alain Charcosset, Sylvain Santoni and Dominique de Vienne 42
Investigation of the effect of genetic background on QTL expression using three connected RIL populations --Alain Charcosset, Mathilde Causse and André Gallais 44
Gif/Yvette, France and Orsay, France
Locating QTLs for carbon metabolism and early growth, using candidate gene approach --Mathilde Causse and Jean Paul Rocher 44
Johnston, Iowa and La Jolla, California and Wageningen, The Netherlands
Associations among inbred lines of maize using RFLP and DNA amplification technologies (AFLP and AP-PCR), and correlations with pedigree, F1 yield and heterosis --Stephen Smith, Stella Luk, Bruno Sobral, Salah Muhawish, Johann Peleman and Marc Zabeau 45
KIRKSVILLE, MISSOURI
Distribution of carotenoids and Y1 mRNA in maize kernels --Brent Buckner and Diane Janick-Buckner 45
Carotenoid content in the endosperm of pale yellow and white kernels that are homozygous for a recessive allele of Y1 --Brent Buckner, Lian A. Bonds and Diane Janick-Buckner 46
kishinev, moldova
Transgressive segregation in the progeny of a cross between two inducers of maize maternal haploids --S. T. Chalyk, V. G. Bylich and O D. Chebotar 47
The influence of chronic gibberellin treatment on the expression of the heterochronic mutation Cg2 --N. V. Krivov and V. N. Lysikov 48
Expressivity of the heterochronic mutation Cg2 and its correlation with gene dose --N. V. Krivov 48
The interaction between genes suppressing heterochronic mutant Cg2 manifestation and the cytoplasm genome --N. V. Krivov 48
The effect of the chromosome 1 segment marked by the Adh1 locus on quantitative traits --A. A. Chernov, M. E. Mihailov and S. V. Ursul 49
Mutagenic effects of laser radiation and 6-mercaptopurine on seedlings --V. K. Burilkov, V. M. Paschenko and V. N. Lysikov 50
krasnodar, russia
Effect of growth environment on development of Zea x Tripsacum hybrid kernels --E. Erygina and A. Mashnenkov 51
Mass induction of maternal haploids in corn --O. A. Shatskaya, E. R. Zabirova, V. S. Shcherbak and M. V. Chumak 51
Autodiploid lines as sources of haploid spontaneous diploidization in corn --O. A. Shatskaya, E. R. Zabirova and V. S. Shcherbak 51
llavallol, argentina
Cytological studies in alloplasmic lines of maize --L. Poggio, C. A. Naranjo, C. L. M. Rosato and L. B. Mazoti 52
Meiotic behavior of maize B chromosomes in the native race "Pisingallo" from NW Argentina --A. M. Chiavarino, L. Poggio and C. A. Naranjo 52
Development of waxy maize inbred lines --V. R. Corcuera and C. A. Naranjo 53
Evaluation of protein content in a maize native race from Argentina --V. R. Corcuera and C. A. Naranjo 54
Cytogenetic abnormalities in callus and plants derived from one maize embryo after 60 months in culture --M. del C. Molina and M. D. Garcia 54
london, ontario, canada
Expression of some maize 18 kDa HSPs result from the translation at internal AUG codons --J. Roger H. Frappier, Robert A. Bouchard, David B. Walden and Burr G. Atkinson 55
In situ hybridization of 18 kDa HSP antisense RNA in maize root tips using digoxigenin detection --R. I. Greyson, E. Banisikowska and D. B. Walden 55
RI mapping of two ubiquitin sequences in maize --Dan Maillet, Burr G. Atkinson and David B. Walden 56
RFLP analysis of genotypic variation in callus --K. J. Bates and D. B. Walden 56
Analysis of environmental effects on RFLP stability in maize inbreds --A. S. Richman and D. B. Walden 57
madison, wisconsin
The absence of debranching enzyme activity and the presence of phytoglycogen in the germinating seeds of sugary1 mutants and commercial sweet corns --David Pan and Oliver E. Nelson 57
mexico city, mexico
Evaluation of tropical inbred lines for resistance to Fusarium moniliforme ear rot --D. Jeffers, S. K. Vasal, S. McLean, G. Srinivasan 58
Evidence for the tri-hybrid origin of Tripsacum andersonii Gray -- Marc Barré, Julien Berthaud, Diego González-de-León and Yves Savidan 58
MILAN, ITALY
Identification of a RAPD marker associated with Rf3 --Renato Tarchini, Andrea Rossi, Mario Enrico Pè and Mirella Sari Gorla 59
Mapping QTLs for pollen thermotolerance in recombinant inbreds --Carla Frova, Michela Bossolasco and Mirella Sari Gorla 60
milan, italy and metaponto, italy
Sequence analysis of an opaque2 mutant of Zea mays --B. Lazzari, P. Ciceri, F. Cellini and A. Viotti 60
moscow, russia
Pollen-specific peroxidase Px2 --Emil E. Khavkin and M. V. Zabrodina 61
moscow, russia and columbia, missouri
Are there clusters of growth-related genes in maize? --Emil E. Khavkin and Ed Coe 61
munich, germany
Cytochrome P450 enzymes of the maize seedling --Monika Frey, Ralf Kliem, Heinz Saedler and Alfons Gierl 62
new delhi, india
Genetic characterization of R-mb:cc, a mutable derivative from R-mb --V. Niral, B. M. Prasanna and K. R. Sarkar 63
Tassel maturation and R-mb:cc expression --V. Niral, B. M. Prasanna and K. R. Sarkar 64
Anthocyanin pattern formation in vitro --V. Niral, B. M. Prasanna and K. R. Sarkar 64
Stabilization of high haploid inducer lines --K. R. Sarkar, A. Pandey, P. Gayen, Jasbir Kaur Madan, Rajesh Kumar and J. K. S. Sachan 64
Chromosome doubling in haploids through colchicine --P. Gayen, Jasbir Kaur Madan, Rajesh Kumar and K. R. Sarkar 65
Morphometric characters of seed in relation to callusing ability (%) and callus growth --Jasbir Kaur Madan, P. Gayen and K. R. Sarkar 65
Effect of silver nitrate on callusing ability --Jasbir Kaur Madan, P. Gayen and K. R. Sarkar 66
Meiotic studies on haploids --P. Gayen, J. K. S. Sachan, Jasbir Kaur Madan and K. R. Sarkar 66
Somatic pairing in maize and teosinte --J. K. S. Sachan, K. R. Sarkar and Ryuso Tanaka 66
Amphidiploid theory of maize origin - revisited --J. K. S. Sachan, M. S. Ramesha, P. Gayen and Vinita Lakkawar 67
Centromeric fusion and knob fusion in maize --S. Dash, P. Gayen, Vinita Lakkawar and J. K. S. Sachan 67
Translocation heterozygosity in Coix --P. Gayen, J. K. S. Sachan, Rajesh Kumar and K. R. Sarkar 68
Comparative pollen grain size in the tribe Maydeae --T. M. Shivakumar, Rajesh Kumar and J. K. S. Sachan 68
Interracial differences in mechanical properties of the cob in relation to knob composition --J. K. S. Sachan and Y. Nath 68
Restructuring maize plant type for higher productivity --J. K. S. Sachan 69
new haven, connecticut
A microsatellite linked to the ts2 locus --Alejandro Calderon-Urrea and Stephen L. Dellaporta 70
Normal, ILlinois
A study of the progeny of monosomic-4 plants in maize --N. I. Teissonniere, D. F. Weber and M. C. Schneerman 70
Normal, ILlinois and Columbia, Missouri
Mapping the centromere of chromosome 4 in maize using a telocentric for 4S --W. Lee, D. F. Weber, M. C. Schneerman, and G. Doyle 71
Northfield, Minnesota
Illustrating multigene mapping data in a spreadsheet format --Edward Weck 71
NORWICH, UK
QTL for drought responses in an F2 population --Steve Quarrie, Claude Lebreton, Vesna Lazic-Jancic and Andrew Steed 73
OAKLAND, CAlifornia
Light requirement for anthocyanin pigmentation of C aleurones --Hugo K. Dooner and Edward Ralston 74
pascani, moldova
The pattern of distribution of the allele Bg-3449 in inbred Zpl 2077/54-14 --Vladimir V. Koterniak 75
Piracicaba, sao paulo, brazil and Campinas, brazil
Selection of plants resistant to S-2-aminoethyl-L-cysteine --Ricardo A. Azevedo and Paulo Arruda 75
Isolation of aspartate kinase from Coix lacryma-jobi --Juverlandi Lugli and Ricardo A. Azevedo 77
piracicaba, sao paulo, brazil and Lancaster, United Kingdom
Aspartate kinase activity extracted from seedlings of the ask1 mutant --Ricardo A. Azevedo and Peter J. Lea 77
PISCATAWAY, NEW JERSEY
Quantitative extraction of pericarp pigments --O. Prem Das, Margaret Morales and Joachim Messing 79
Effect of P-pr on pigmentation conditioned by P-rr --O. Prem Das, Barton Scott, John Lena and Joachim Messing 79
A heritable interaction between P-pr and P-rr --O. Prem Das and Joachim Messing 80
Mapping of a novel d-zein and a proposal for revising nomenclature of the d-class zeins --Sanjay Swarup and Joachim Messing 81
Analysis of dzs23, which encodes the highest methionine containing zein --Sanjay Swarup, Sumita Chaudhuri and Joachim Messing 81
pittsburgh, pennsylvania
A new maize ring chromosome - ring10:A1179 --Mary Alleman 82
pusa, bihar, india
Embryoid formation from cultured anthers of two inbreds and their hybrid --Arti Kumari, Harsh Kumar, S. K. T. Nasar and M. Kumar 83
A simple method for pollen karyotyping in maize --Arti Kumari, S. K. T. Nasar, M. Kumar and H. Kumar 83
Cytotoxicity of a herbicide in maize --M. Prasad, M. Kumar, H. Kumar and S. K. T. Nasar 83
Effect of media on callusing and rhizogenesis from cultured root explants of genotype TUXP237-2 --Ashok Kumar, Harsh Kumar, S. K. T. Nasar and M. Kumar 84
Differential tissue culture response of seedling explants of cv. Swan --Harsh Kumar and M. Kumar 84
raipur, india and New delhi, india
Size and distribution of stomata in maize and its wild relatives --G. Chandel, Rajesh Kumar and S. Katiyar 84
Pollen size variation in Coix --G. Chandel, S. Katiyar, Rajesh Kumar and J. K. S. Sachan 85
raleigh, north carolina
Linkage of RFLP markers to genes controlling resistance to southern corn rust --J. B. Holland, D. V. Uhr and M. M. Goodman 85
St. Paul, minnesota
Teosinte glume architecture1 controls silica deposition in the glumes of maize --Jane E. Dorweiler and John Doebley 85
Suppressor of sessile spikelets1 (Sos1): a dominant mutant affecting inflorescence development --John Doebley, Beth Kent and Adrian Stec 87
Teosinte branched1 and the origin of maize --John Doebley and Adrian Stec 88
Photos of teosinte glume architecture1 -- Jane Dorweiler and John Doebley 89
Terminal ear1 and the origin of maize -- John Doebley 91
Genes encoding methionine-rich proteins: Chromosomal location of a duplicate locus of zps10/(22) --Todd L. Krone and Ronald L. Phillips 92
Identification and mapping of maize acetyl-CoA carboxylase genes --Margaret Egli, Sheila Lutz, Dave Somers and Burle Gengenbach 92
Threonine-overproducing, lysine-insensitive aspartate kinase (Ask2) map location --Gary J. Muehlbauer, Burle G. Gengenbach and David A. Somers 93
Identification of point mutations which confer lysine-insensitivity to maize dihydrodipicolinate synthase --Jonathan M. Shaver, Douglas C. Bittel, David A. Somers and Burle G. Gengenbach 93
ST. PAUL, MINNESOTA and BELTSVILLE, MARYLAND
Aspartate kinase-homoserine dehydrogenase bifunctional enzyme --Gary J. Muehlbauer, David A. Somers, Benjamin F. Matthews and Burle G. Gengenbach 94
STANFORD, CALIFORNIA
MuDR-like elements in Zapalote chico maize --Christine Warren and Virginia Walbot 94
Structure and regulation of the Bronze-2 promoter --John P. Bodeau and Virginia Walbot 95
Shielding and repair: responses to ultraviolet radiation --Ann E. Stapleton and Virginia Walbot 96
Bronze2 and related genes: a clue to the function of the BZ2 protein? --Kathleen A. Marrs and Virginia Walbot 97
Anthocyanin genotypes in an A188 background, and their pigment phenotypes in embryogenic calli --John P. Bodeau and Virginia Walbot 98
stuttgart, germany
Herbicide resistance as a marker in screening for maternal haploids -- H. H. Geiger, S. R. Roux and S. Deimling 99
taejon, korea
Genetics of super thin pericarp --Insup Lee, Bongho, Choe, Wonkoo Lee and Heebong Lee 100
Tillers taller than the main stem are heritable --Heebong Lee, Wonkoo Lee, Insup Lee, Bongho Choe and Seungkeunn Chung 100
Tillering and prolific inbreds --Bongho Choe, Heebong Lee, Wonkoo Lee and Heechung Ji 100
Taichung, taiwan
A new type of non-chromosomal stripe from Taiwanese maize --Bor-yaw Lin and Hao-Jan Yu 100
TUCSON, ARIZONA and GAINESVILLE, FLORIDA and HAYWARD, CALIFORNIA
Compilation of mapping/sequencing results for randomly selected maize cDNAs --Tim Helentjaris, Ivone Torres-Jerez, Bo Shen, Newton Carneiro, Becky Stevenson, Tom McCreery, 101
Jeff Habben, Brian Larkins, Rob Ferl, Ernie Almira and Chris Baysdorfer 101
Stocks and new factors --G. F. Sprague 105
Silencing of restorer-of-fertility genes of cms-S -- S. Gabay-Laughnan and J. R. Laughnan 105
A phototoxin in maize leaves, disease resistance? --Robert Tuveson and Dale M. Steffensen 106
URBANA, ILLINOIS
Three-point linkage data for su1, lw4, and gl4 on chromosome 4 --Philip S. Stinard 107
Three-point linkage data for pr1, lw3, and v2 on chromosome 5 --Philip S. Stinard 107
URBANA, ILLINOIS and AMES, IOWA
o12 and cp2 are allelic to dek7 --Philip S. Stinard and Patrick S. Schnable 107
New alleles of et2 and su3 --Philip S. Stinard and Patrick S. Schnable 107
The new, improved TB-9Lc --Philip S. Stinard and Patrick S. Schnable 108
victoria, bc, canada
Notes from a corner in Victoria --E. D. Styles 108
waltham, massachusetts
The identity of Mga (maize glume architecture) on 4S confused with a multiple allelic series at the Tu (tunicate) locus --Walton C. Galinat 109
Significant differences between populations grown from single pd compared with paired Pd spikelet seed borne in variegated arrangements on individual ears. --Walton C. Galinat 109
WEST LAFAYETTE, INDIANA and URBANA, ILLINOIS and SLATER, IOWA
QTLs for degree of pollen-silk discordance, expression of disease lesion mimic, and leaf curl response to drought --B.E. Zehr, J.W. Dudley and G.K. Rufener 110
WEST LAFAYETTE, INDIANA and SALT LAKE CITY, UTAH
Regions of genomic similarity among four 'Stiff Stalk' inbred lines as measured by multiple restriction enzymes in RFLP analysis --B.E. Zehr and S. Wright 111
wuhan, china
Allozyme polymorphisms within and among local varieties of maize in Southwestern China --H. Lu, Y. L. Zheng, J. S. Li, X. Z. Xiong and J. L. Liu 113
zhengzhou, china
Chromosome linkage study of Rf locus for cms-C --Shaojiang Chen and Weicheng Chen 113

III. USING MAIZE IN K-12 EDUCATION 115

IV. MAILING LIST 117

V. MAIZE GENETICS COOPERATION STOCK CENTER 143





Please Note: Notes submitted to the Maize Genetics Cooperation Newsletter may be cited only with consent of the authors

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