Implication of the C terminus of the Prunus necrotic ringspot virus movement protein in cell-to-cell transport and in its interaction with the coat protein

Umbravirus-like RNA viruses are capable of independent systemic plant infection in the absence of encoded movement proteins

The signature feature of all plant viruses is the encoding of movement proteins (MPs) that supports the movement of the viral genome into adjacent cells and through the vascular system. The recent discovery of umbravirus-like viruses (ULVs), some of which only encode replication-associated proteins, suggested that they, as with umbraviruses that lack encoded capsid proteins (CPs) and silencing suppressors, would require association with a helper virus to complete an infection cycle. We examined the infection properties of 2 ULVs: citrus yellow vein associated virus 1 (CY1), which only encodes replication proteins, and closely related CY2 from hemp, which encodes an additional protein (ORF5CY2) that was assumed to be an MP. We report that both CY1 and CY2 can independently infect the model plant Nicotiana benthamiana in a phloem-limited fashion when delivered by agroinfiltration. Unlike encoded MPs, ORF5CY2 was dispensable for infection of CY2, but was associated with faster symptom development. Examination of ORF5CY2 revealed features more similar to luteoviruses/poleroviruses/sobemovirus CPs than to 30K class MPs, which all share a similar single jelly-roll domain. In addition, only CY2-infected plants contained virus-like particles (VLPs) associated with CY2 RNA and ORF5CY2. CY1 RNA and a defective (D)-RNA that arises during infection interacted with host protein phloem protein 2 (PP2) in vitro and in vivo, and formed a high molecular weight complex with sap proteins in vitro that was partially resistant to RNase treatment. When CY1 was used as a virus-induced gene silencing (VIGS) vector to target PP2 transcripts, CY1 accumulation was reduced in systemic leaves, supporting the usage of PP2 for systemic movement. ULVs are therefore the first plant viruses encoding replication and CPs but no MPs, and whose systemic movement relies on a host MP. This explains the lack of discernable helper viruses in many ULV-infected plants and evokes comparisons with the initial viruses transferred into plants that must have similarly required host proteins for movement.

An Evolutionary Perspective of Codon Usage Pattern, Dinucleotide Composition and Codon Pair Bias in Prunus Necrotic Ringspot Virus

Prunus necrotic ringspot virus (PNRSV) is a significant virus of ornamental plants and fruit trees. It is essential to study this virus due to its impact on the horticultural industry. Several studies on PNRSV diversity and phytosanitary detection technology were reported, but the content on the codon usage bias (CUB), dinucleotide preference and codon pair bias (CPB) of PNRSV is still uncertain. We performed comprehensive analyses on a dataset consisting of 359 coat protein (CP) gene sequences in PNRSV to examine the characteristics of CUB, dinucleotide composition, and CPB. The CUB analysis of PNRSV CP sequences showed that it was not only affected by natural selection, but also affected by mutations, and natural selection played a more significant role compared to mutations as the driving force. The dinucleotide composition analysis showed an over-expression of the CpC/GpA dinucleotides and an under-expression of the UpA/GpC dinucleotides. The dinucleotide composition of the PNRSV CP gene showed a weak association with the viral lineages and hosts, but a strong association with viral codon positions. Furthermore, the CPB of PNRSV CP gene is low and is related to dinucleotide preference and codon usage patterns. This research provides reference for future research on PNRSV genetic diversity and gene evolution mechanism.

Plant virus movement proteins originated from jelly-roll capsid proteins

Numerous, diverse plant viruses encode movement proteins (MPs) that aid the virus movement through plasmodesmata, the plant intercellular channels. MPs are essential for virus spread and propagation in distal tissues, and several unrelated MPs have been identified. The 30K superfamily of MPs (named after the molecular mass of tobacco mosaic virus (TMV) MP, the classical model of plant virology) is the largest and most diverse MP variety, represented in 16 virus families, but its evolutionary origin remained obscure. Here, we show that the core structural domain of the 30K MPs is homologous to the jelly-roll domain of the capsid proteins (CPs) of small RNA and DNA viruses, in particular, those infecting plants. The closest similarity was observed between the 30K MPs and the CPs of the viruses in the families Bromoviridae and Geminiviridae. We hypothesize that the MPs evolved via duplication or horizontal acquisition of the CP gene in a virus that infected an ancestor of vascular plants, followed by neofunctionalization of one of the paralogous CPs, potentially through the acquisition of unique N- and C-terminal regions. During the subsequent coevolution of viruses with diversifying vascular plants, the 30K MP genes underwent explosive horizontal spread among emergent RNA and DNA viruses, likely permitting viruses of insects and fungi that coinfected plants to expand their host ranges, molding the contemporary plant virome.

Comparative Genome Analysis of Old World and New World TYLCV Reveals a Biasness toward Highly Variable Amino Acids in Coat Protein

Begomoviruses, belonging to the family Geminiviridae and the genus Begomovirus, are DNA viruses that are transmitted by whitefly Bemisia tabaci (Gennadius) in a circulative persistent manner. They can easily adapt to new hosts and environments due to their wide host range and global distribution. However, the factors responsible for their adaptability and coevolutionary forces are yet to be explored. Among BGVs, TYLCV exhibits the broadest range of hosts. In this study, we have identified variable and coevolving amino acid sites in the proteins of Tomato yellow leaf curl virus (TYLCV) isolates from Old World (African, Indian, Japanese, and Oceania) and New World (Central and Southern America). We focused on mutations in the coat protein (CP), as it is highly variable and interacts with both vectors and host plants. Our observations indicate that some mutations were accumulating in Old World TYLCV isolates due to positive selection, with the S149N mutation being of particular interest. This mutation is associated with TYLCV isolates that have spread in Europe and Asia and is dominant in 78% of TYLCV isolates. On the other hand, the S149T mutation is restricted to isolates from Saudi Arabia. We further explored the implications of these amino acid changes through structural modeling. The results presented in this study suggest that certain hypervariable regions in the genome of TYLCV are conserved and may be important for adapting to different host environments. These regions could contribute to the mutational robustness of the virus, allowing it to persist in different host populations.

The coat protein of the ilarvirus prunus necrotic ringspot virus mediates long-distance movement

The coat protein (CP) of plant viruses generally has multiple functions involving infection, replication, movement and pathogenicity. Functions of the CP of prunus necrotic ringspot virus (PNRSV), the causal agent of several threatening diseases of Prunus fruit trees, are poorly studied. Previously, we identified a novel virus in apple, apple necrotic mosaic virus (ApNMV), which is phylogenetically related to PNRSV and probably associated with apple mosaic disease in China. Full-length cDNA clones of PNRSV and ApNMV were constructed, and both are infectious in cucumber (Cucumis sativus L.), an experimental host. PNRSV exhibited higher systemic infection efficiency with more severe symptoms than ApNMV. Reassortment analysis of genomic RNA segments 1-3 found that RNA3 of PNRSV could enhance the long-distance movement of an ApNMV chimaera in cucumber, indicating the association of RNA3 of PNRSV with viral long-distance movement. Deletion mutagenesis of the PNRSV CP showed that the basic motif from amino acids 38 to 47 was crucial for the CP to maintain the systemic movement of PNRSV. Moreover, we found that arginine residues 41, 43 and 47 codetermine viral long-distance movement. The findings demonstrate that the CP of PNRSV is required for long-distance movement in cucumber, which expands the functions of ilarvirus CPs in systemic infection. For the first time, we identified involvement of Ilarvirus CP protein during long-distance movement.

Spontaneous Mutation in the Movement Protein of Citrus Leprosis Virus C2, in a Heterologous Virus Infection Context, Increases Cell-to-Cell Transport and Generates Fitness Advantage

Previous results using a movement defective alfalfa mosaic virus (AMV) vector revealed that citrus leprosis virus C (CiLV-C) movement protein (MP) generates a more efficient local movement, but not more systemic transport, than citrus leprosis virus C2 (CiLV-C2) MP, MPs belonging to two important viruses for the citrus industry. Here, competition experiment assays in transgenic tobacco plants (P12) between transcripts of AMV constructs expressing the cilevirus MPs, followed by several biological passages, showed the prevalence of the AMV construct carrying the CiLV-C2 MP. The analysis of AMV RNA 3 progeny recovered from P12 plant at the second viral passage revealed the presence of a mix of progeny encompassing the CiLV-C2 MP wild type (MP^WT) and two variants carrying serines instead phenylalanines at positions 72 (MP^S72F) or 259 (MP^S259F), respectively. We evaluated the effects of each modified residue in virus replication, and cell-to-cell and long-distance movements. Results indicated that phenylalanine at position 259 favors viral cell-to-cell transport with an improvement in viral fitness, but has no effect on viral replication, whereas mutation at position 72 (MP^S72F) has a penalty in the viral fitness. Our findings indicate that the prevalence of a viral population may be correlated with its greater efficiency in cell-to-cell and systemic movements.

Unravelling the involvement of cilevirus p32 protein in the viral transport

Citrus leprosis (CL) is a severe disease that affects citrus orchards mainly in Latin America. It is caused by Brevipalpus-transmitted viruses from genera Cilevirus and Dichorhavirus. Currently, no reports have explored the movement machinery for the cilevirus. Here, we have performed a detailed functional study of the p32 movement protein (MP) of two cileviruses. Citrus leprosis-associated viruses are not able to move systemically in neither their natural nor experimental host plants. However, here we show that cilevirus MPs are able to allow the cell-to-cell and long-distance transport of movement-defective alfalfa mosaic virus (AMV). Several features related with the viral transport were explored, including: (i) the ability of cilevirus MPs to facilitate virus movement on a nucleocapsid assembly independent-manner; (ii) the generation of tubular structures from transient expression in protoplast; (iii) the capability of the N- and C- terminus of MP to interact with the cognate capsid protein (p29) and; (iv) the role of the C-terminus of p32 in the cell-to-cell and long-distance transport, tubule formation and the MP-plasmodesmata co-localization. The MP was able to direct the p29 to the plasmodesmata, whereby the C-terminus of MP is independently responsible to recruit the p29 to the cell periphery. Furthermore, we report that MP possess the capacity to enter the nucleolus and to bind to a major nucleolar protein, the fibrillarin. Based on our findings, we provide a model for the role of the p32 in the intra- and intercellular viral spread.

The 28 Ser Amino Acid of Cucumber Mosaic Virus Movement Protein Has a Role in Symptom Formation and Plasmodesmata Localization

Cucumber mosaic virus (CMV, Cucumovirus, Bromoviridae) is an economically significant virus infecting important horticultural and field crops. Current knowledge regarding the specific functions of its movement protein (MP) is still incomplete. In the present study, potential post-translational modification sites of its MP were assayed with mutant viruses: MP/S28A, MP/S28D, MP/S120A and MP/S120D. Ser28 was identified as an important factor in viral pathogenicity on Nicotiana tabacum cv. Xanthi, Cucumis sativus and Chenopodium murale. The subcellular localization of GFP-tagged movement proteins was determined with confocal laser-scanning microscopy. The wild type movement protein fused to green fluorescent protein (GFP) (MP-eGFP) greatly colocalized with callose at plasmodesmata, while MP/S28A-eGFP and MP/S28D-eGFP were detected as punctate spots along the cell membrane without callose colocalization. These results underline the importance of phosphorylatable amino acids in symptom formation and provide data regarding the essential factors for plasmodesmata localization of CMV MP.

Dichorhaviruses Movement Protein and Nucleoprotein Form a Protein Complex That May Be Required for Virus Spread and Interacts in vivo With Viral Movement-Related Cilevirus Proteins

Brevipalpus-transmitted viruses (BTVs) belong to the genera Dichorhavirus and Cilevirus and are the main causal agents of the citrus leprosis (CL) disease. In this report, we explored aspects related to the movement mechanism mediated by dichorhaviruses movement proteins (MPs) and the homologous and heterologous interactions among viral proteins related to the movement of citrus leprosis-associated viruses. The membrane-spanning property and topology analysis of the nucleocapsid (N) and MP proteins from two dichorhaviruses revealed that the MPs are proteins tightly associated with the cell membrane, exposing their N- and C-termini to the cytoplasm and the inner part of the nucleus, whereas the N proteins are not membrane-associated. Subcellular localization analysis revealed the presence of dichorhavirus MPs at the cell surface and in the nucleus, while the phosphoproteins (P) were located exclusively in the nucleus and the N proteins in both the cytoplasm and the nucleus. Co-expression analysis with the MP, P, and N proteins showed an interaction network formed between them. We highlight the MP capability to partially redistribute the previously reported N-P core complex, redirecting a portion of the N from the nucleus to the plasmodesmata at the cell periphery, which indicates not only that the MP might guide the intracellular trafficking of the viral infective complex but also that the N protein may be associated with the cell-to-cell movement mechanism of dichorhaviruses. The movement functionality of these MPs was analyzed by using three movement-defective infectious systems. Also, the MP capacity to generate tubular structures on the protoplast surface by ectopic expression was analyzed. Finally, we evaluated the in vivo protein–protein interaction networks between the dichorhavirus MP and/or N proteins with the heterologous cilevirus movement components, which suggest a broad spectrum of interactions, highlighting those among capsid proteins (CP), MPs, and Ns from citrus leprosis-associated viruses. These data may aid in understanding the mixed infection process naturally observed in the field caused by distinct BTVs.

Key checkpoints in the movement of plant viruses through the host

Plant viruses cannot exploit any of the membrane fusion-based routes of entry described for animal viruses. In addition, one of the distinctive structures of plant cells, the cell wall, acts as the first barrier against the invasion of pathogens. To overcome the rigidity of the cell wall, plant viruses normally take advantage of the way of life of different biological vectors. Alternatively, the physical damage caused by environmental stresses can facilitate virus entry. Once inside the cell and taking advantage of the characteristic symplastic continuity of plant cells, viruses need to remodel and/or modify the restricted pore size of the plasmodesmata (channels that connect plant cells). In a successful interaction for the virus, it can reach the vascular tissue to systematically invade the plant. The connections between the different cell types in this path are not designed to allow the passage of molecules with the complexity of viruses. During this process, viruses face different cell barriers that must be overcome to reach the distal parts of the plant. In this review, we highlight the current knowledge about how plant RNA viruses enter plant cells, move between them to reach vascular cells and overcome the different physical and cellular barriers that the phloem imposes. Finally, we update the current research on cellular organelles as key regulator checkpoints in the long-distance movement of plant viruses.

Molecular Biology of Prune Dwarf Virus-A Lesser Known Member of the Bromoviridae but a Vital Component in the Dynamic Virus-Host Cell Interaction Network

Prune dwarf virus (PDV) is one of the members of Bromoviridae family, genus Ilarvirus. Host components that participate in the regulation of viral replication or cell-to-cell movement via plasmodesmata are still unknown. In contrast, viral infections caused by some other Bromoviridae members are well characterized. Bromoviridae can be distinguished based on localization of their replication process in infected cells, cell-to-cell movement mechanisms, and plant-specific response reactions. Depending upon the genus, "genome activation" and viral replication are linked to various membranous structures ranging from endoplasmic reticulum, to tonoplast. In the case of PDV, there is still no evidence of natural resistance sources in the host plants susceptible to virus infection. Apparently, PDV has a great ability to overcome the natural defense responses in a wide spectrum of plant hosts. The first manifestations of PDV infection are specific cell membrane alterations, and the formation of replicase complexes that support PDV RNA replication inside the spherules. During each stage of its life cycle, the virus uses cell components to replicate and to spread in whole plants, within the largely suppressed cellular immunity environment. This work presents the above stages of the PDV life cycle in the context of current knowledge about other Bromoviridae members.

Identification and characterization of privet leaf blotch-associated virus, a novel idaeovirus

A novel virus has been identified by next-generation sequencing (NGS) in privet (Ligustrum japonicum L.) affected by a graft-transmissible disease characterized by leaf blotch symptoms resembling infectious variegation, a virus-like privet disease with an unclear aetiology. This virus, which has been tentatively named 'privet leaf blotch-associated virus' (PrLBaV), was absent in non-symptomatic privet plants, as revealed by NGS and reverse transcription-polymerase chain reaction (RT-PCR). Molecular characterization of PrLBaV showed that it has a segmented genome composed of two positive single-stranded RNAs, one of which (RNA1) is monocistronic and codes for the viral replicase, whereas the other (RNA2) contains two open reading frames (ORFs), ORF2a and ORF2b, coding for the putative movement (p38) and coat (p30) proteins, respectively. ORF2b is very probably expressed through a subgenomic RNA starting with six nucleotides (AUAUCU) that closely resemble those found in the 5'-terminal end of genomic RNA1 and RNA2 (AUAUUU and AUAUAU, respectively). The molecular signatures identified in the PrLBaV RNAs and proteins resemble those of Raspberry bushy dwarf virus (RBDV), currently the only member of the genus Idaeovirus. These data, together with phylogenetic analyses, are consistent with the proposal of considering PrLBaV as a representative of the second species in the genus Idaeovirus. Transient expression of a recombinant PrLBaV p38 fused to green fluorescent protein in leaves of Nicotiana benthamiana, coupled with confocal laser scanning microscopy assays, showed that it localizes at cell plasmodesmata, strongly supporting its involvement in viral movement/trafficking and providing the first functional characterization of an idaeovirus encoded protein.

The functional analysis of distinct tospovirus movement proteins (NSM) reveals different capabilities in tubule formation, cell-to-cell and systemic virus movement among the tospovirus species

The lack of infectious tospovirus clones to address reverse genetic experiments has compromised the functional analysis of viral proteins. In the present study we have performed a functional analysis of the movement proteins (NS_M) of four tospovirus species Bean necrotic mosaic virus (BeNMV), Chrysanthemum stem necrosis virus (CSNV), Tomato chlorotic spot virus (TCSV) and Tomato spotted wilt virus (TSWV), which differ biologically and molecularly, by using the Alfalfa mosaic virus (AMV) model system. All NS_M proteins were competent to: i) support the cell-to-cell and systemic transport of AMV, ii) generate tubular structures on infected protoplast and iii) transport only virus particles. However, the NS_M of BeNMV (one of the most phylogenetically distant species) was very inefficient to support the systemic transport. Deletion assays revealed that the C-terminal region of the BeNMV NS_M, but not that of the CSNV, TCSV and TSWV NS_M proteins, was dispensable for cell-to-cell transport, and that all the non-functional C-terminal NS_M mutants were unable to generate tubular structures. Bimolecular fluorescence complementation analysis revealed that the C-terminus of the BeNMV NS_M was not required for the interaction with the cognate nucleocapsid protein, showing a different protein organization when compared with other movement proteins of the '30K family'. Overall, our results revealed clearly differences in functional aspects among movement proteins from divergent tospovirus species that have a distinct biological behavior.

Patellins 3 and 6, two members of the Plant Patellin family, interact with the movement protein of Alfalfa mosaic virus and interfere with viral movement

Movement proteins (MPs) encoded by plant viruses interact with host proteins to facilitate or interfere with intra- and/or intercellular viral movement. Using yeast two-hybrid and bimolecular fluorescence complementation assays, we herein present in vivo evidence for the interaction between Alfalfa mosaic virus (AMV) MP and Arabidopsis Patellin 3 (atPATL3) and Patellin 6 (atPATL6), two proteins containing a Sec14 domain. Proteins with Sec14 domains are implicated in membrane trafficking, cytoskeleton dynamics, lipid metabolism and lipid-mediated regulatory functions. Interestingly, the overexpression of atPATL3 and/or atPATL6 interfered with the plasmodesmata targeting of AMV MP and correlated with reduced infection foci size. Consistently, the viral RNA levels increased in the single and double Arabidopsis knockout mutants for atPATL3 and atPATL6. Our results indicate that, in general, MP-PATL interactions interfere with the correct subcellular targeting of MP, thus rendering the intracellular transport of viral MP-containing complexes less efficient and diminishing cell-to-cell movement.

Two basic (hydrophilic) regions in the movement protein of Parietaria mottle virus have RNA binding activity and are required for cell-to-cell transport

The movement protein (MP) of parietaria mottle virus (PMoV) is required for virus cell-to-cell movement. Bioinformatics analysis identified two hydrophilic non-contiguous regions (R1 and R2) rich in the basic amino acids lysine and arginine and with the predicted secondary structure of an α-helix. Different approaches were used to determine the implication of the R1 and R2 regions in RNA binding, plasmodesmata (PD) targeting and cell-to-cell movement. EMSA (Electrophoretic Mobility Shift Assay) showed that both regions have RNA-binding activity whereas that mutational analysis reported that either deletion of any of these regions, or loss of the basic amino acids, interfered with the viral intercellular movement. Subcellular localization studies showed that PMoV MP locates at PD. Mutants designed to impeded cell-to-cell movement failed to accumulate at PD indicating that basic residues in both R1 and R2 are critical for binding the MP at PD.

The molecular biology of ilarviruses

Ilarviruses were among the first 16 groups of plant viruses approved by ICTV. Like Alfalfa mosaic virus (AMV), bromoviruses, and cucumoviruses they are isometric viruses and possess a single-stranded, tripartite RNA genome. However, unlike these other three groups, ilarviruses were recognized as being recalcitrant subjects for research (their ready lability is reflected in the sigla used to create the group name) and were renowned as unpromising subjects for the production of antisera. However, it was recognized that they shared properties with AMV when the phenomenon of genome activation, in which the coat protein (CP) of the virus is required to be present to initiate infection, was demonstrated to cross group boundaries. The CP of AMV could activate the genome of an ilarvirus and vice versa. Development of the molecular information for ilarviruses lagged behind the knowledge available for the more extensively studied AMV, bromoviruses, and cucumoviruses. In the past 20 years, genomic data for most known ilarviruses have been developed facilitating their detection and allowing the factors involved in the molecular biology of the genus to be investigated. Much information has been obtained using Prunus necrotic ringspot virus and the more extensively studied AMV. A relationship between some ilarviruses and the cucumoviruses has been defined with the recognition that members of both genera encode a 2b protein involved in RNA silencing and long distance viral movement. Here, we present a review of the current knowledge of both the taxonomy and the molecular biology of this genus of agronomically and horticulturally important viruses.

Ilarviruses of Prunus spp.: a continued concern for fruit trees

Prunus spp. are affected by a large number of viruses, causing significant economic losses through either direct or indirect damage, which results in reduced yield and fruit quality. Among these viruses, members of the genus Ilarvirus (isometric labile ringspot viruses) occupy a significant position due to their distribution worldwide. Although symptoms caused by these types of viruses were reported early in the last century, their molecular characterization was not achieved until the 1990s, much later than for other agronomically relevant viruses. This was mainly due to the characteristic liability of virus particles in tissue extracts. In addition, ilarviruses, together with Alfalfa mosaic virus, are unique among plant viruses in that they require a few molecules of the coat protein in the inoculum in order to be infectious, a phenomenon known as genome activation. Another factor that has made the study of this group of viruses difficult is that infectious clones have been obtained only for the type member of the genus, Tobacco streak virus. Four ilarviruses, Prunus necrotic ringspot virus, Prune dwarf virus, Apple mosaic virus, and American plum line pattern virus, are pathogens of the main cultivated fruit trees. As stated in the 9th Report of the International Committee on Taxonomy of Viruses, virions of this genus are "unpromising subjects for the raising of good antisera." With the advent of molecular approaches for their detection and characterization, it has been possible to get a more precise view of their prevalence and genome organization. This review updates our knowledge on the incidence, genome organization and expression, genetic diversity, modes of transmission, and diagnosis, as well as control of this peculiar group of viruses affecting fruit trees.

Contribution of topology determinants of a viral movement protein to its membrane association, intracellular traffic, and viral cell-to-cell movement

The p7B movement protein (MP) of Melon necrotic spot virus (MNSV) is a single-pass membrane protein associated with the endoplasmic reticulum (ER), the Golgi apparatus (GA), and plasmodesmata (Pd). Experimental data presented here revealed that the p7B transmembrane domain (TMD) was sufficient to target the green fluorescent protein (GFP) to ER membranes. In addition, the short extramembrane regions of p7B were essential for subsequent ER export and transport to the GA and Pd. Microsomal partitioning and bimolecular fluorescence assays supported a type II topology of p7B in planta. Mutations affecting conventional determinants of p7B membrane topology, such as the TMD secondary structure, the overall hydrophobicity profile, the so-called "aromatic belt," and the net charge distribution on either side of the TMD, were engineered into infectious RNAs to investigate the relationship between the MP structure and MNSV cell-to-cell movement. The results revealed that (i) the overall hydrophobic profile and the α-helix integrity of the TMD were relevant for virus movement, (ii) modification of the net charge balance of the regions flanking both TMD sides drastically reduced cell-to-cell movement, (iii) localization of p7B to the GA was necessary but not sufficient for virus movement, and (iv) membrane insertion was essential for p7B function in virus movement. Our results therefore indicate that MNSV cell-to-cell movement requires sequential transport of p7B from the ER via the GA to Pd, which is modulated by a combination of several signals with different strengths in the extramembrane regions and TMD of the MP.