![]() ![]() Embryo development remains arrested until the fertilized ovary is buried in the soil with the help of a specialized organ called the peg or gynophore. Peanuts produce aerial flowers but subterranean fruits (pods). The peanut seeds are rich in vegetable oils, proteins, vitamins and minerals. The peanut (Arachis hypogaea L.) is one of the world’s most important economic oilseed crops. These studies have demonstrated that IGT family genes play a role in regulating plant architecture in response to both light and gravity stimuli. The expression of AtIGT genes was also found to respond differentially to alterations in light signaling, and the loss of several LAZY and DRO genes in Arabidopsis resulted in a lack of branch angle reaction to light stimuli 25. ![]() A report showed that the expression of AtTAC1, which modulated plant architecture in response to photosynthetic signals, was light dependent 24. Several studies have shown that light and gravity signals function concurrently to shape plant architecture 21, 22, 23. TAC1 showed a similar expression pattern to LAZY1 19, which modulated plant branch growth angle, but had opposite functions 19, 20. ![]() TAC1 was described as a key QTL that controlled the production of compact and erect tillers in rice 18. LAZY4 is involved in gravitropic responses via auxin signaling and promotes deep rooting in rice 17. LAZY4/ DEEPER ROOTING 1 ( DRO1) was identified as a key QTL controlling deep rooting in rice 16. LAZY1 is a crucial regulator of negative gravitropism, and its loss leads to the formation of wide-angled branches in Arabidopsis thaliana 15. Over the decades, the LAZY1, which responsible for lazy traits 12, 13, 14 have been identified. The lazy1 traits, initially described in the 1930s, exhibited a prostrate growth habit in rice and maize 10, 11. Much less information about the domain III and IV is available 7, 8, 9. Any mutation in this directly resulted in the loss of function of LAZY1 4, 6. The IGT conserved domain II contains the family-specific GφL (A/T) IGT sequence. Domain I located at N terminus, and it is necessary for anchoring AtLAZY1 at the plasma membrane 6. TAC1 lacks this motif (domain V) which is known to be essential for functions of LAZY1 and LAZY4 5. This arrangement was characterized by a short exon encoding two amino acids and the last exon encoding a short peptide including ethylene-responsive amphiphilic repression (EAR) motif containing transcriptional repressors 3, 4. Additionally, a unique intron–exon arrangement was also detected for IGT genes. Nevertheless, 5 short conserved motifs, called I–V domains, have been identified in IGT family proteins, but not all were present in all members of the family 3. IGT genes have relatively low levels of sequence conservation across gene-family members. The IGT gene family comprises a set of genes ( LAZY1-6) and TILLER ANGLE CONTROL 1 ( TAC1). The IGT gene family, which is identified based on a conserved motif (GφL(A/T)IGT), has been observed to play a significant role in regulating gravitropism and shaping the structure of plants 2. Optimizing plant architecture has been demonstrated as one of the best methods to improve planting density, stress-tolerance and overall productivity of crops 1. This study may facilitate functional studies of the IGT genes in peanut. Furthermore, qRT-PCR analysis showed that the expression of several AhIGT genes, like AhTAC1-2/4, was light-dependent, indicating that these genes may regulate plant architecture in response to light signals. The cis-element analysis revealed that the light-responsive elements accounted for most of all cis-acting elements. ![]() Transcript profile analysis suggested that AhTAC1 could potentially be involved gynophore (‘peg’) penetration into the soil. The analysis of conserved motifs, GO annotation, and transcript profile suggested that AhLAZY1-3 may play roles in gravity sensing and shaping peanut plant architecture. Chromosomal localization and synteny analyses showed that AhIGTs were unevenly localized on 9 chromosomes and that segmental duplication and purifying selection may have played important roles in the evolution of AhIGT genes. AhIGTs within the same subfamily maintained a consistent motif composition. Gene structure, conserved domain analyses indicated all AhIGTs were observed to share a similar exon–intron distribution pattern. In the current study, 13 AhIGT genes were identified and classified into three groups based on their phylogenetic relationship. However, limited amount of information is available about IGT family genes in peanuts ( Arachis hypogaea). IGT family genes play essential roles in shaping plant architecture. ![]()
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |