Role of apoplastic calcium during germination and initial stages of seedling establishment in Vigna radiata seeds.

Calcium (Ca2+) is implicated in the initial phase of seed germination and seedling establishment. It is stored complexed with phytic acid during seed development and released by phytase action during germination. We observed phytase activity 18 h post-imbibition (PI) in Vigna seeds, while radicle protrusion occurred approximately 12 h PI. Cotyledon protein extracts prepared 4, 8, 16 and 24 h PI, subjected to Ca2+ immobilized metal affinity chromatography (Ca2+ IMAC), revealed the presence of Ca2+ binding proteins (CaBPs), while Ca2+-dependent amylase activity peaked 18 h PI, implying Ca2+ presence before its release from Ca-phytate, indicating an alternative source of Ca2+. Vigna cotyledon cell-wall preparations 4 h and 24 h PI, titrated against alkali, revealed high cation-binding capacity, and seeds 4 h PI demonstrated high rates of H+ extrusion. Ca2+-binding capacity as well as cell-wall bound Ca2+, measured in cotyledon cell-wall preparations from unimbibed seeds as well as seeds 24 h PI, using a novel competitive chelation technique, showed a marked decline in Ca2+ binding capacity, as well as cell-wall bound Ca2+. Imbibition in the presence of chelators, Ca2+-channel blockers, and H+-pump inhibitors, interfered with germination and radical extension. Further, EDTA-treated cotyledon protein extracts separated on Ca2+IMAC showed a larger CaBP peak than control cotyledon extracts. Pooled fractions clearly showed Ca2+-induced extrinsic fluorescence with anilino -napthalene sulfonate. The results strongly implicate the apoplast may be a major source of Ca2+ in the initial phase of germination and seedling establishment in Vigna seeds.

Development of parthenote following in vivo transfer of embryos in Capra hircus.

The aim of this study is to generate parthenogenetic embryos from chemically activated in vitro matured caprine oocytes and to study the in vivo developmental potency of such embryos. The parthenogenetic embryos (2-8 and 16 cells to morula stage) were surgically transferred in 26 recipients. Pregnancy in recipients following embryo transfer was monitored by ultrasonography. The recipient aborted a foetus on day 34 post transfer. Sexing of parthenogenetic foetus showed a single band of amelogenin gene indicating female cell DNA. Microsatellite analysis revealed that the recipient has not contributed genetically to the parthenogenetic foetus confirming the identity of aborted foetus of parthenogenetic origin. The authors believe that this is the first authentic report on in vivo development of parthenogenetic foetus in Capra hircus.

Impact of norgestomet supplementation during early luteal phase on subsequent luteal profiles and conception rate in buffalo: a preliminary study.

The current study was aimed to establish the impact of progesterone supplementation (norgestomet progestagen) between days 4 to 10 post-ovulation on subsequent luteal profile and conception rate in buffaloes. The 28 Murrah buffaloes of second to fourth parity, having normal reproductive organs, were estrus synchronized by double PGF(2α) protocol at 11 days apart. The buffaloes were inseminated during mid- to late estrus and thereafter repeated at 24 h interval. The buffaloes were randomly assigned into two groups: (1) control (no treatment, n = 14) and (2) treatment group (CRESTAR ear implant, n = 14). The CRESTAR ear implant (3 mg, norgestomet progestagen) was inserted subcutaneous between days 4 to 10 post-ovulation. The ovaries were scanned at estrus and thereafter on days 4, 10, 16, 21, and 40 post-ovulation to examine the preovulatory follicle (POF) and corpus luteum (CL) diameter. Each ultasonography was followed by blood sample collection for analysis of plasma progesterone concentrations following ovulation. The conception rate was similar (p > 0.05) between treated and control buffaloes. The pregnant buffalo of the control group had larger (p < 0.05) POF diameter than nonpregnant counterparts. The CL diameter was similar (p > 0.05) in both treated and untreated control as well as in their pregnant and nonpregnant buffaloes of the respective groups. The plasma progesterone concentrations were higher (p < 0.05) in the treatment group on the day 10 post-ovulation as compared to the control buffaloes. It is concluded that norgestomet supplementation had no impact on conception rate and CL diameter but enhances the plasma progesterone concentrations following treatment in buffaloes.

Study of genetic polymorphism in solvent exposed population and its correlation to in vitro effect of trichloroethylene on lymphocytes.

Trichloroethylene (TCE) is major industrial pollutant that contaminate environment. Its exposure may lead to hepato-renal toxicity along with the cancer progression. Although extensive research is done on its toxicity still not much is known about its genotoxic potential on humans in relation to genetic polymorphism. Cytochrome P450 (CYP P-450) and glutathione-S-transferases (GSTs) are important in cellular detoxification of TCE. Variations in gene sequences result in population specific regional genetic variations (polymorphism). Genotyping of CYP1A1, GSTM1, GSTT1 and GSTP1 polymorphism was performed in 220 normal and 97 solvent-exposed individuals from northern part of India using real time PCR, PCR and restriction digestion techniques. The parameters examined to study genotoxicity were chromosomal aberration (CA) and cytokinesis block micronucleus assay (CBMN) in lymphocyte culture in vitro. The observed average frequencies for GSTM1 (null) and GSTT1 (null) were 41, 22 and 12.7%, respectively in normal subjects whereas frequencies of CYP1A1/GSTP1 with (ile/ile) or (ile/val) or(val/val) were found to be 76.2/52, 21.4/42.1 and 2.4/5.9% respectively. It was further observed that the frequencies of above genes were found to be similar in solvent exposed groups. The distribution frequencies of GST genes, when compared with other reports from various regions of India show variations. In vitro TCE exposure (2, 4 and or 6 mM) did not show any significant genotoxic effect. TCE maybe toxic due to its metabolite.