With current advances in genomics, several technological processes have been generated, resulting in improvement in different segments of molecular research involving prokaryotic and eukaryotic systems. A widely used contribution is the identification of new genes and their functions, which has led to the elucidation of several issues concerning cell regulation and interactions. For this, increase in the knowledge generated from the identification of promoters becomes considerably relevant, especially considering that to generate new technological processes, such as genetically modified organisms, the availability of promoters that regulate the expression of new genes is still limited. Considering that this issue is essential for biotechnologists, this paper presents an updated review of promoters, from their structure to expression, and focuses on the knowledge already available in eukaryotic systems. Information on current promoters and methodologies available for studying their expression are also reported.

-ISSR markers were used to discriminate intraspecific peanut accessions, and to utilize the most divergents aiming to generate variability by crossing. The accessions were grown in a greenhouse and at 20 days after sowing, leaves were collected for DNA extraction and subsequent ISSR-PCR tests. Ten primers were used to generate mono and polymorphic bands. Among them, the most contributive to discriminating accessions were UBC-818 and UBC-842, which respectively produced 14 and 12 bands, and a polymorphism rate of 64 and 83%. The primers UBC-847 and UBC-858 generated few bands, with over 60% monomorphic and low contribution to studies of access discrimination using ISSR markers. Three distinct clusters were formed in the dendrogram, among which two genotypes with greater divergence, represented by cultivar BR 1 (short cycle and upright) and line LViPE-06 (late cycle and runner), were selected for hybridization to generate genetic variability. The resulting F 2 progenies showed broad genetic variability, with large contribution to selection procedures for the to assist selection procedures in peanut. Based on the results obtained, it was possible to confirm the contribution of molecular tools to assist selection procedures in peanut.

A B S T R A C TConsidering that the NCED gene acts on the biosynthetic cascade of ABA, a hormone involved in the functioning of stomata and consequently in the regulation of transpiration, the aim of this research was to analyze the expression of this gene in colored cotton genotypes subjected to water stress at the beginning of plant growth. Four colored cotton genotypes were used, subjected to two managements, with and without water stress, beginning the treatments when the blade of the first true leaves reached an area that allowed the evaluation of gas exchange. For the studies of the expression of the NCED gene, via RT-qPCR, leaves were collected on three distinct dates: at 4 and 6 days of water stress, and after the plants regained their turgor. The differential expression of NCED was found in all genotypes, with higher levels of expression related to six days of water stress. When the stomatal conductance was around 25%, there was overexpression in the genotype CNPA 2009. Expressão do gene NCED em genótipos de algodoeiros coloridos submetidos a estresse hídrico R E S U M O Considerando que o gene NCED atua na cascata biossintética do ABA, hormônio envolvido no funcionamento dos estômatos e, consequentemente, na regulação da transpiração objetivou-se, com esta pesquisa, analisar a expressão desse gene em genótipos de algodão colorido submetidos a déficit hídrico no início do crescimento das plantas. Foram utilizados quatro genótipos de algodão colorido (CNPA 2009-6, CNPA 2009-11, BRS SAFIRA e CNPA 2009) submetidos a dois manejos sem e com estresse hídrico iniciando-se quando o limbo das primeiras folhas verdadeiras atingiu uma área que permitiu a avaliação de trocas gasosas. Para os estudos de expressão do gene NCED via RT-qPCR foram coletadas folhas em três datas distintas: aos quatro e seis dias de estresse hídrico e após as plantas recuperarem a turgescência. Em todos os genótipos foi constatada expressão diferencial de NCED com maior nível de expressão relativa aos seis dias de estresse; quando a condutância estomática estava em torno de 25% ocorreu superexpressão no genótipo CNPA 2009.13 seguido de CNPA 2009.6, BRS SAFIRA e em CNPA 2009.11 confirmando os dados obtidos na PCR semiquantitativa. O gene NCED está envolvido na resposta ao estresse hídrico na fase vegetativa de algodoeiro colorido.

ABSTRACT.A subtractive cDNA library from cotton buds was constructed to prospect for differentially expressed genes related to early bud development. A library was constructed and 768 cDNA sequences were obtained, comprising 168 clusters, with 126 contigs and 42 singlets. Both the Gossypium as well as Arabidopsis databases were utilized for the in silico analysis, since some genes identified in cotton have not yet been studied for functionality, although they have homology with genes from other species. The transcriptome revealed a large number of transcripts, some of them with unknown function, and others related to pollen development, pollen tubes, ovules, and fibers at different stages. The most populated contig was identified as fiber from 0-10 days after anthesis, with 12 reads. The success and novelty rates generated from the library were 67 and 51%, respectively. The information obtained here will provide a framework for research on functional cotton genomics.

Cotton has high adaptability to adverse conditions; however, one of the main factors causing production loss is water deficits. To adapt to these conditions, plants go through a series of changes, many of them driven by genes that are expressed to increase drought tolerance. We examined the expression profile of the MYB60 and GUSP1 genes, which are involved in the abiotic stress pathway, focusing on drought tolerance. Four Upland and Mocó genotypes were submitted to water stress during early growth and further evaluated at 50% (phase 1) and 80% (phase 2) of stomata enclosure. Plants were previously phenotyped, based on vegetative, physiological and biochemical traits. Expression of GUSP1 and MYB60 transcripts was estimated by qRT-PCR. Plants were grown in 288 mL pots in a greenhouse and further submitted to water stress during 25 days. Although Mocó cotton is considered tolerant to drought and upland cotton is known to be drought-sensitive; we ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 18 (4): gmr18319 V.G.L. Batista et al. 2 found a different behavior in these genotypes. Mocó 1 was very sensitive to the imposed water deficiency stress, with severe reductions in leaf number, stem diameter and weight of roots and canopy, while Delta Opal (Upland) presented the smallest reductions in growth. Expression of GUSP1 transcripts was higher in all stressed genotypes, in both phases, during the water stress period, with the genotype Mocó 2, presenting the highest level of expression, while MYB60 transcripts were high expressed only in phase 1, decreasing in phase 2. Considering that differences in the expression of MYB60 can be detected earlier, because the peak of expression occurred at phase 1 of water stress, it is worth investigating the genetic diversity in cotton germplasm to select genotypes with drought tolerance and to estimate the relation with the expression of MYB60, since Mocó genotypes were considered tolerant, but in this work a Mocó 1 genotype presented drought-sensitive characteristics.