Induction of direct somatic embryogenesis and plant regeneration from mature cotyledon explants of Arachis hypogea L

A plant regeneration method via direct somatic embryogenesis was achieved in cotyledon explants derived from mature, dry seeds of Arachis hypogaea L. According to histological observations, somatic embryogenesis was induced directly without any intervening callus on MS medium supplemented with different concentrations of BAP along with 2.68 μM NAA after 4 weeks of culture. The incidence of somatic embryogenesis was greater at the distal end of the cotyledon than the remaining portion. The range of embryogenesis frequency was 10.7 to 80.2 %, depending on the BAP concentration in combination with NAA. The best response was observed on MS medium containing 22.19 μM BAP along with 2.68 μM NAA. The embryos matured and germinated on fresh medium with or without growth regulators. A large percentage of somatic embryos developed into normal plants producing viable seeds. Some embryos produced flower buds on the germination medium

Oral immunization of cattle with hemagglutinin protein of rinderpest virus expressed in transgenic peanut induces specific immune responses

Rinderpest is an acute, highly contagious often fatal disease of large and small ruminants, both domestic and wild. Global eradication of rinderpest needs a robust, safe and cost-effective vaccine. The causative agent, rinderpest virus (RPV) is an important member of the genus Morbillivirus in the Paramyxoviridae family. We have generated transgenic peanut (Arachis hypogea L.) plants expressing hemagglutinin protein of RPV and report here, the induction of immune responses in cattle following oral feeding with transgenic leaves expressing hemagglutinin protein without oral adjuvant. Hemagglutinin-specific antibody was detected in the serum as confirmed by immunohistochemical staining of virus-infected cells, and in vitro neutralization of virus infectivity. Oral delivery also resulted in cell-mediated immune responses

Effect of <i>Alternaria </i>pathotoxin(s) on expression of p⁵³-like apoptotic protein in <span style="font-size:14.0pt;line-height:115%;font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";color:black;mso-ansi-language:EN-IN; mso-fareast-language:EN-IN;mso-bidi-language:HI" lang="EN-IN">calli and leaves of <i>Brassica campestris</i></span>

89-94<span style="font-size:14.0pt;line-height: 115%;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">Possible involvement of apoptosis was investigated in pathotoxin-treated and nutritionally-depleted in vitro cultured calli by comparing levels of p53-like protein. Antibodies raised against human p53 were used to detect and quantify p53 in B.campestris. Expression of p53-like protein increased from proliferating to static growth stage and reached to constant level at decaying stage. Both ELISA and dot immuno-binding assay showed that p53 -like protein was over expressed in toxin treated and nutritionally depleted calli. Almost similar changes were seen in senescent damage in Brassica species indicating involvement of p53 dependent pathways<span style="font-size:14.0pt;line-height:115%;font-family:Fd28117-Identity-H; mso-fareast-font-family:" times="" new="" roman";mso-bidi-font-family:fd28117-identity-h;="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">.</span

Arabidopsis Transcriptome Reveals Control Circuits Regulating Redox Homeostasis and the Role of an AP2 Transcription Factor1[W][OA]

Sensors and regulatory circuits that maintain redox homeostasis play a central role in adjusting plant metabolism and development to changing environmental conditions. We report here control networks in Arabidopsis (Arabidopsis thaliana) that respond to photosynthetic stress. We independently subjected Arabidopsis leaves to two commonly used photosystem II inhibitors: high light (HL) and 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU). Microarray analysis of expression patterns during the period of redox adjustment to these inhibitors reveals that 20% and 8% of the transcriptome are under HL and DCMU regulation, respectively. Approximately 6% comprise a subset of genes common to both perturbations, the redox responsive genes (RRGs). A redox network was generated in an attempt to identify genes whose expression is tightly coordinated during adjustment to homeostasis, using expression of these RRGs under HL conditions. Ten subnetworks were identified from the network. Hierarchal subclustering of subnetworks responding to the DCMU stress identified novel groups of genes that were tightly controlled while adjusting to homeostasis. Upstream analysis of the promoters of the genes in these clusters revealed different motifs for each subnetwork, including motifs that were previously identified with responses to other stresses, such as light, dehydration, or abscisic acid. Functional categorization of RRGs demonstrated involvement of genes in many metabolic pathways, including several families of transcription factors, especially those in the AP2 family. Using a T-DNA insertion in one AP2 transcription factor (redox-responsive transcription factor 1 [RRTF1]) from the RRGs, we showed that the genes predicted to be within the subnetwork containing RRTF1 were changed in this insertion line (Δrrtf1). Furthermore, Δrrtf1 showed greater sensitivity to photosynthetic stress compared to the wild type

Expression of hemagglutinin protein of Rinderpest virus in transgenic pigeon pea [Cajanus cajan (L.) Millsp.] plants

Rinderpest virus is the causative agent of a devastating, often fatal disease in wild and domestic bovids that is endemic in Africa, the Middle East and South Asia. The existing live attenuated vaccine is heat-labile, and thus there is a need for the development of new strategies for vaccination. This paper reports the development of transgenic pigeon pea [Cajanus cajun (L.) Millsp.] expressing one of the protective antigens, the hemagglutinin (H) protein of Rinderpest virus. A 2-kb fragment containing the coding region of the H protein was cloned into pBI121 and mobilized into Agrobacterium tumefaciens strain EHA105. Embryonic axes and cotyledonary nodes from germinated seeds of pigeon pea were used for transformation. The presence of the transgene in transgenic plants was confirmed by Southern blots, and the specific transcription of the marker gene in the plants was demonstrated by reverse transcription-polymerase chain reaction. Integration of the H gene into the pigeon pea genome was confirmed by Southern hybridization. The expression of the H protein in the transgenic lines was confirmed by Western blot analysis using a polyclonal monospecific antibody to the H protein. The highest level of expression of the hemagglutinin protein in leaves of pigeon pea was 0.49% of the total soluble protein. The transgenic plants were fertile and the transgene expressed in the progeny

Expression of hemagglutinin protein of Rinderpest virus in transgenic pigeon pea [Cajanus cajan (L.) Millsp.] plants

Rinderpest virus is the causative agent of a devastating, often fatal disease in wild and domestic bovids that is endemic in Africa, the Middle East and South Asia. The existing live attenuated vaccine is heat-labile, and thus there is a need for the development of new strategies for vaccination. This paper reports the development of transgenic pigeon pea [Cajanus cajun (L.) Millsp.] expressing one of the protective antigens, the hemagglutinin (H) protein of Rinderpest virus. A 2-kb fragment containing the coding region of the H protein was cloned into pBI121 and mobilized into Agrobacterium tumefaciens strain EHA105. Embryonic axes and cotyledonary nodes from germinated seeds of pigeon pea were used for transformation. The presence of the transgene in transgenic plants was confirmed by Southern blots, and the specific transcription of the marker gene in the plants was demonstrated by reverse transcription-polymerase chain reaction. Integration of the H gene into the pigeon pea genome was confirmed by Southern hybridization. The expression of the H protein in the transgenic lines was confirmed by Western blot analysis using a polyclonal monospecific antibody to the H protein. The highest level of expression of the hemagglutinin protein in leaves of pigeon pea was 0.49% of the total soluble protein. The transgenic plants were fertile and the transgene expressed in the progeny

Agrobacterium-mediated genetic transformation and regeneration of transgenic plants from cotyledon explants of groundnut (Arachis hypogaea L.) via somatic embryogenesis

An efficient transformation protocol was developed for groundnut (Arachis hypogaea L.) plants. Precultured cotyledons were co-cultured with Agrobacterium tumefaciens strain LBA 4404 harbouring the binary vector pBI121 containing the uidA (GUS) and nptII genes for 2 days and cultured on an embryo induction medium containing 0.5 mg/l NAA, 5.0 mg/l BAP, 75 mg/ml kanamycin and 300 mg/ml cefotaxime. The putatively transformed embryos were transferred to the medium with reduced kanamycin (50 mg/ml) for further development. Prolific shoots developed from these embryos on a MS medium containing 0.5 mg/l BAP and 50 mg/ml kanamycin with a transformation efficiency of 47%. The elongated kanamycin-resistant shoots were subsequently rooted on the MS medium supplemented with 1.0 mg/l IBA. The transgenic plants were later established in plastic cups. A strong GUS activity was detected in the putatively transformed plants by histochemical assay. Transformation was confirmed by PCR analyses. Integration of T-DNA into nuclear genome of transgenic plants was further confirmed by Southern hybridization with nptII gene probe. A large number of transgenic plants were obtained in this study. This protocol allows effective transformation and quick regeneration via embryogenesis

Induction of direct somatic embryogenesis and plant regeneration from mature cotyledon explants of Arachis hypogaea L

A plant regeneration method via direct somatic embryogenesis was achieved in cotyledon explants derived from mature, dry seeds of Arachis hypogaea L. According to histological observations, somatic embryogenesis was induced directly without any intervening callus on MS medium supplemented with different concentrations of BAP along with 2.68 m M NAA after 4 weeks of culture. The incidence of somatic embryogenesis was greater at the distal end of the cotyledon than the remaining portion. The range of embryogenesis frequency was 10.7 to 80.2%, depending on the BAP concentration in combination with NAA. The best response was observed on MS medium containing 22.19 m M BAP along with 2.68 m M NAA. The embryos matured and germinated on fresh medium with or without growth regulators. A large percentage of somatic embryos developed into normal plants producing viable seeds. Some embryos produced flower buds on the germination medium

Induction of direct somatic embryogenesis and plant regeneration from mature cotyledon explants of Arachis hypogaea L.

A plant regeneration method via direct somatic embryogenesis was achieved in cotyledon explants derived from mature, dry seeds of Arachis hypogaea L. According to histological observations, somatic embryogenesis was induced directly without any intervening callus on MS medium supplemented with different concentrations of BAP along with 2.68 μM NAA after 4 weeks of culture. The incidence of somatic embryogenesis was greater at the distal end of the cotyledon than the remaining portion. The range of embryogenesis frequency was 10.7 to 80.2%, depending on the BAP concentration in combination with NAA. The best response was observed on MS medium containing 22.19 μM BAP along with 2.68 μM NAA. The embryos matured and germinated on fresh medium with or without growth regulators. A large percentage of somatic embryos developed into normal plants producing viable seeds. Some embryos produced flower buds on the germination medium